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The article offers solutions to different publications of zoological nomenclature for the Asian elephant, Elephas maximus Linnaeus, 1758. It notes that the problem of competing interpretations of nomenclature can be solved by publishing the online document and the paper-print document on the same date without any modifications to the content. It cites that 'ahead of print' online publications should use the exact same document for the initial online publication.

A recent phylogenetic analysis of the Myxinidae based on the 16S rRNA gene resulted in synonymization of Paramyxine with Eptatretus. This created homonymy of Paramyxine fernholmi with Eptatretus fernholmi and Paramyxine wisneri with Eptatretus wisneri. In order to resolve this nomenclatural dilemma, we made a more extensive phylogenetic assessment of the Myxinidae and examined the nomenclature of the family. We used 75 sequences (37 of which new for this study) of a 561 bp fragment of the 16S rRNA gene, representing 33 species, and 72 sequences (37 of which new for this study) of a 687 bp fragment of the cytochrome c oxidase subunit I ( COI) gene, representing 23 species, to reconstruct the phylogeny of Myxinidae. The monophyly of the subfamily Myxininae, traditionally characterized by having a single pair of external gill openings, was rejected (0.50 Bayesian posterior probability) by the 16S analysis, but supported by the COI and combined COI+ 16S analyses (0.99 and 0.81 Bpp, respectively). The monophyly of the subfamily Eptatretinae, characterized by having several pairs of external gill openings, was not supported by the 16S analysis and rejected by the COI and combined COI+ 16S analysis due to the placement of Eptatretus lopheliae as the earliest branch of Myxinidae (0.71 and 0.57 Bpp, respectively). Eptatretus lopheliae and Eptatretus rubicundus formed a monophyletic group and were allocated to a new genus, Rubicundus, characterized by the presence of an elongated tubular nostril and reddish coloration. A new monotypic subfamily, Rubicundinae, was proposed for Rubicundus. The synonymy of the genera Paramyxine and Quadratus with Eptatretus was confirmed. E. fernholmi is renamed Eptatretus luzonicus. Eptatretus wisneri was renamed Eptatretus bobwisneri. Petromyzon cirrhatus Forster, 1801, Homea banksii Fleming, 1822, and Bdellostoma forsteri Müller, 1836 are synonyms, but no type specimens are known to exist. Petromyzon cirrhatus was designated as type species of Eptatretus, conserving present usage. Gastrobranchus dombeyi Shaw, 1804 has priority over other names for Chilean myxinids. Bdellostoma stoutii was designated as type species of Polistotrema Gill. The validity of the Western Atlantic Myxine limosa as distinct from the Eastern Atlantic Myxine glutinosa was confirmed. [ABSTRACT FROM AUTHOR]

Scanning electron microscopy and light microscopy demonstrate that the mature thread cells in Eptatretus deani and Myxine glutinosa consist of a single, coiled thread up to 10 cm long. Mature thread cells apparently loose the cell membrane within the slime gland before expulsion. Thus the old idea that rupture of the cell membrane causes the uncoiling in sea water is no longer tenable. If the thread cells are transferred without additional fluid to a microscope slide, no uncoiling occurs until sea water or distilled water is added when the process occurs rapidly; however, in double strength sea water uncoiling is slowed down. In tetrahydrofuran or glycerin there is no uncoiling in 100 % or 50 % solutions; however in 5 % solutions uncoiling occurs slowly. Thus the availability of adequate amounts of water seems to be necessary for uncoiling. Presumably, water acts directly on the thread, causing the organelle to straighten and thus uncoil. The defensive value of the slime production is discussed. [ABSTRACT FROM AUTHOR]

The ependymal cells of both dorsal arid ventral walls lining the lumen of the neurohypophysis of the hagfish, Eptatretus burgeri, absorb peroxidase injected into the third ventricle. Peroxidase diffuses rapidly into the connective tissue separating the neurohypophysis from the adenohypophysis. and also into the connective tissue located between the cell nests of the adenohypophysis. [ABSTRACT FROM AUTHOR]

Ripe females and males of Eptatretus burgeri were kept in cages both in the sea and in the aquaria for about 2 months of the normal spawning period around October. All the 9 ripe females in the sea ovulated all their eggs (200) and deposited 178 of them. Only 5 eggs were ovulated and deposited in the aquaria, although there were 17 ripe females and some of them were injected with various hormones in an effort to induce ovulation. No eggs were fertilized. A peculiar surface pattern of hexagonal ridges is described around the entrance of the micropylar canal on the bottom of the micropylar funnel in the ovulatcd eggs. [ABSTRACT FROM AUTHOR]

The pro-adenohypophysis (pro-AH) of migrating adult river lamprey, Lampetra fluviatilis, has been examined from October. when the gonads are developing slowly, until May, when the sexual maturation is completed. Two granulated cell types are dominating. One is chromophobic (C2, 95 nm), the other is basophilic (B1-B3) and probably gonadotropic. The mean diameter of the basophil secretory granules increases from 150 nm in October to 220 nm in April and May. The staining affinity of a rare, granulated cell type (D, 115 nm) has riot been established. No acidophil cells are found in the pro-AH. The ultrastructural characteristics of the lead hematoxylin positive cells found sometimes in paraffin sections are unknown. Non-glandular stellate cells are common. They contain microfilaments, are probably contractile, and transform to phagocytes during the last months before spawning. This phagocytosis involves only the basophil cells. It is suggested that the stellate cells in this way destroy excess hormone. All cell types in the pituitary accumulate large irregular lipid droplets during the last month before spawning. These lipid droplets seem to be expelled from residual bodies as an end product of autolysis and phagocytosis. [ABSTRACT FROM AUTHOR]

Intraperitoneal injection of mammalian thyrotropin-releasing hormone (TRH) caused hypertrophy of possible thyrotropic cells in the pituitary gland of the telcost, Chasmichthys dolichognathus. The epithelial cells of the thyroid follicles also appeared hypertrophic after the TRH injection. On the other hand, in the hagfish, Eptatretus burgeri, TRH injection had no effect either on the cytological appearance of the adenohypophysis or on the thyroidal activity in terms of serum thyroxine concentration arid epithelial cell height. [ABSTRACT FROM AUTHOR]

Two endocrine cell types, PbH + and PAS + cells, were recognized in the pars intermedia (PI) of the roach. Leuciscus rutilus, by light and electron microscopy. They can be distinguished by the appearance of their secretory granules. The PAS + cells stain with toluidine blue in semithin sections as opposed to the PbH + cells. After 5 days' treatment with metopirone the PhH + cells are highly activated whereas the PAS + cells show no response. The PbH + cells are assumed to produce MSH. In roaches adapted to diluted sea water (10 ‰) the transfer to fresh water for 1- -1 ½ hours or reset-pine injections for the same period had no notable effect on neither cell type. Three kinds of axons innervate the P1. Two of these, which have granules averaging 111 nm arid 151 nm in diameter. originate in the nucleus preopticus (NPO). The third type of axons has granules of an average Size of 74 nm and is probably aminergic. The glia cells in this part of the neurohypophysis (NH) are granular pituicytes, which are innervated by all three axon types. The border between the NH and the PT is composed of a double basement membrane from which a network extends into the NH. This network, the basement membrane and the capillaries are the main sites for the terminations of the axons although nerve fibers also invade the endocrine tissue. Only axon type 3 was observed to synapse frequently with the PbH + cells. [ABSTRACT FROM AUTHOR]

Three endocrine cell types were recognized in the proximal pars distalis (PPD) of the roach, Leuciscus rutilus, by electron microscopy. Two of these cell types are basophilic and assumed to be gonadotropic. The third cell type is acidophilic and its similarity to somatotropic (STH) cells is evident. Green fluorescent cells corresponding to cells with dense core vesicles of about 85 nm are scattered between the PPD and the proximal neurohypophysis (PNH). Their possible content of a catecholamine was demonstrated with microspectrofluorometric analyses. Four axon types with granules 65, 81, 110 and 137 nm in average diameter terminate at the basement membrane. Only fibers with granules of 81 nm enter the PPD to make synapses with the STH cells. Extensions of the basement membrane are continuous with the perivascular space and penetrate the endocrine tissue. It is postulated that axon terminals on the basement membrane are functionally equivalent to synaptic contacts on the endocrine cells. Axon type 4 has granules which in sizes correspond to those of cells in lateral and ventrolateral parts of the nucleus lateralis tuberis (NLT). A similar correlation is possible between axon type 3 and other cells in the NLT. This is in accordance with earlier conclusions of a regulation of the gonadotropic cells from the lateral (posterior) parts of the NLT. [ABSTRACT FROM AUTHOR]

Three different endocrine cell types were identified by electron microscopy in the rostral pars distalis (RPD) of the roach, Leuciscus rutilus. The cells which are characterized by the morphology and sizes of their secretory granules are assumed to secrete prolactin. ACTH and TSH Prolactin cells occur in two forms which could be separated on account of the sizes of their granules. Intra-peritoneal injections of reserpine had a strong arid persistent effect 24 hours after the treatment. The prolactin cells with small granules reacted with a marked release of secretion. The border of the RPD is composed of a so-called double basement membrane in contact with the perivascular spaces and forms extensive ramifications into the rostral neurohypophysis (RNH). Nerve fibers of different categories terminate at the border and its network in the RNH. Substances released from these terminals may influence the endocrine cells of the RPD. The ACTII cells and the Prolactin cells are innervated by axons with granules less than 100 nm. The nomenclature of type `A' fibers and `B' fibers is discussed because it was difficult to make a reliable discrimination of the fibers and their nature by the sizes of their granules. However, four types of nerve fibers were distinguished in connection with the RPD although the presence of more types was indicated, in all four types the size variations of the granules are great and overlapping. The average sizes of the granules in these fibers are 157, 114, 119 and 81 nm. The origin of the nerve fibers innervating the RPD is discussed. All morphological data indicate a complex hypothalamic control of the RPD of the roach. [ABSTRACT FROM AUTHOR]

Localization of steroidogenic cells possibly existing in the hagfish wa attempted using the following 3 methods: 1. Injection and autoradio graphic localization of the labelled precursor cholesterol-4-14C, 2. Histo chemical localization of 3β-ol dehydrogenase and other hydroxysteroic dehydrogenases and 3. Electron microscopic analysis of the gonad. It i concluded that if there is any steroid hormone formation in the ova of the hagfish, it is extremely small and is not detectable by the method used here. [ABSTRACT FROM AUTHOR]

A 4.5 cm Myxine embyro is described. The structure of its adenohypophysis suggests that it is derived from a dorsal thickening and proliferation of the nasopharyngical duct epithelium as a homogeneous mass of cells. This process seems to start medially and proceed laterally. The characteristic lobulated appearance of the adult adenohypophysis is caused by a later invasion of connective tissue. Large areas of the ventral brain surface were found to be richly vascularized. No traces of an endostylar arrangement were observed and the thyroid follicles were distinct. [ABSTRACT FROM AUTHOR]

The article discusses about a light microscopic studies on the Nucleus Lateralis Tuberis (NLT) and of the Leuciscus rutilus. The neurosecretory nature of the nucleus lateralis tuberis of fishes has long been recognized but little attention has been given to the function of this interesting structrue. There is morphological evidence that NLT may be involved in the regulation of the fish pituitary. Several early workes described connections between the nucleus and the pituitary, and recently some of them, has demonstrated its connection with the pars distalis in the eel.