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Recent occurrences of Talismania bifurcata (Parr, 1951) and Alepocephalus tenebrosus Gilbert 1891 are described, accompanied by distributional records. Taxonomic affinities are discussed.

36. Alepocephalus Agassizii, new species. A single specimen of Alepocephalus was obtained at Station 338, in 922 fathoms, Lat. 38�� 18' 40" N., Long. 73�� 18' 10" W. This is the fourth species of the genus which has, to date, come up for description: the first, A. rostratus, having been described by Risso from the Mediterranean in 1820; the second, A. niger, from north of Australia, at a depth of 1,400 fathoms, obtained by H. M. S. " Challenger, ������ and described by Gunther in 1878; the third, A. Bairdii, from the Grand Banks of Newfoundland, at a depth of 200 fathoms, described by us in 1879. The former American species having been named in honor of the Director of the U. S. National Museum, we propose to dedicate the one now under consideration to the Curator of the Museum of Comparative Zoology, under the name Alepocephalus Agassizii. Diagnosis. - Body slightly less elongate than in A. Bairdii, its height being contained very slightly more than five times in its length to origin of middle caudal rays, somewhat compressed, its width being about half its height. The least height of the tail is contained twelve times in the length of the l*odv. O O % ��� Scales apparently ovate-lanceolate, parchment-like, smaller than in A. Bairdii: the specimen is almost denuded of scales, and their arrangement in the drawing has been in part made out from their impressions upon the skin. There are ninety scales in the lateral line, ten between lateral line and origin of dorsal, eleven between same and origin of anal. The base of the dorsal is squamose, the anal slightly so, but probably less than in A. Bairdii. Head somewhat compressed, snout conically elongate, the lower jaw slightly produced. Its length is contained three times in the length of the body (in A. Bairdii, 4-J-), slightly exceeding twice the length of the lower jaw, and four times the least height of the tail (in A. Bairdii, less than three). Width of head.slightly less than length of operculum, and times in length of body (12 in A. Bairdii). Length of snout half that of mandible, which is one sixth of total length (i in A. Bairdii). Diameter of orbit in total length of body 10�� times (18 in A. Bairdii), 3i in head (about 4\ in A. Bairdii). The insertion of the dorsal is immediately above the vent; the distance of its origin from the base of middle caudal rays equal to one third of distance from same to anterior margin of orbit, and at a distance from the snout much greater than two thirds the total length of body (about equal in A. Bairdii). The length of its base is equal to one eighth of total length. The origin of the anal is under the second ray of the dorsal; its length of base is slightly more than one seventh of the body length, and is equal to the height of the body at the vent. o %j The ends of the dorsal, anal, and caudal rays are broken off in the specimen before us. Distance of pectoral from snout, equal to J of the body length (slightly more than \ in A. Bairdii) and 4-^ times least height of tail (3 in A. Bairdii). Its length equal to the diameter of orbit and contained 10^ times in total length (10 in A. Bairdii). The origin of the pectoral is close behind the end of the opercular flap, while in A. Bairdii it is separated therefrom by four rows of scales. Distance of ventral from snout considerably less than twice the length of the head. Its length, probably, about one sixth that of the head. Radial formula: D. 15; A. 17; C. 19; P. 11; V. 1, 5 I L. lat. 90. Dentition as in A. Bairdii. Color dark, head and fins nearly black., Published as part of Goode, G. B. & Bean, T. H., 1883, Reports on the results of dredging under the supervision of Alexander Agassiz, on the east coast of the United States, during the summer of 1880, by the U. S. coast survey steamer " Blake, " Commander J. R. Bartlett, U. S. N., commanding., pp. 183-226 in Bulletin of the Museum of Comparative Zoology at Harvard College 10 (5) on pages 218-219, DOI: 10.5281/zenodo.28095

Please note that the text underneath the table “Measurements, in millimetres, and Numbers of Rows of Scales and Fin Rays in Irish specimens of Alepocephalus” on page 44 [182] reads: * Impossible to measure exactly in large individuals of this species.; † Height perhaps slightly increased by pressure during preservation.; ‡ Anterior rays very small and buried in skin, perhaps more numerous., Many of the fishes which inhabit the deeper water of the Atlantic coast are unfamiliar to fishermen, and were not described in the books to which the general reader had ready access in the early 1900s. It was therefore the intention of the authors to give an account and figure; or sketch, of all except the well-known kinds. This is the second report in an occasional series on the fishes of the Irish Atlantic Slope.

Abyssotrema pritchardae gen. et sp. n. is described from the benthic teleost, Alepocephalus agassizi Goode and Bean 1883 (Alepocephalidae), taken from Hudson Canyon in the western North Atlantic. The new genus is placed in the subfamily Monascinae Dollfus 1947 and relationships among Abyssotrema, Elopsium Fischthal and Thomas 1972, and Monascus Looss 1907 are discussed.

THE MID-DEPTHS of the oceans comprise a significant part of the volume of the biosphere, yet the conditions for life here are so different from those encountered by man that it is difficult to appreciate the factors limiting the distribution of the bathypelagic organisms living there. Catch records, however, indicate that many species are restricted in their geographical distribution. An attempt is made here to study the conditions of life in these mid-depths by centering attention on a group of fish that has a worldwide distribution. There are a number of fish groups which could serve for such a study, among them the gonostomiatids and the myetophids. Although these two groups have a wide distribution and occur in large numbers, their taxonomy has not been sufficiently clarified to make a zoogeographic study possible. The genus Chauliodus was chosen because it fulfilled the requirements. It has a world-wide distribution; large numbers of body measurements are available for the comparison of different populations; physical and chemical data are available for the stations at which the specimens were caught. The Stomiatoidei, the suborder to which Chauliodus belongs, can be considered herring-like fish with photophores and extremely large teeth. The genus Chauliodus has been placed in the family Chauliodontidae by Berg (1940), removing it from the Stomiatidae because the inner ear of Chauliodus lacks a lagena, whereas all the other members of that family have one. These two families make up the superfamily Stomiatoidae in the suborder Stomiatoidel. This suborder of the Clupeiformes is characterized by Berg as being "near the Clupeoidei, especially near the Alepocephalidae." (p. 431). Although Chauliodus (Plate 1, p. 120) lacks scales, the pattern of the pigment is such that it forms hexagonal areas in which there is a thin deposit of an opalescent substance, which appears under magnification like guanine crystals. The body is covered by a thick transparent coating containing microscopic spheres of unknown composition. This gelatinous layer forms, in part, the base of the adipose fin, and does not seem to be merely a slime secretion. Brauer (1908) was of the opinion that the gelatinous layer is a part of the corneum of the skin, although his earlier observations had led him to believe that it was a slime secretion. The fang-like teeth (Plate 2) appear admirably suited to the capture of the animals found in the mid-depths, and, indeed, stomach analyses show that Chauliodus feeds on chaetognaths (Clemens and Wilby, 1946) and on macroplanktonic crustacea, probably deep-sea prawns (personal observation). It is tempting to speculate that the prey is lured to the mouth by the many lights of the photophores. These light organs are of three types: microscopic spheres without a pigment layer; large spheres with a pigment coat, reflector and lens; and larger, bell-shaped organs with a pigment coat, lens and reflector. The microscopic photophores are scattered over the dorsal surface of the fish, whereas the larger, pigment-covered spherical organs are found in groups within each hexagonal "scale area," around the eye socket, and in rows along the dorsal surface of the base of the pectoral and pelvic fins, and the base of the dorsal and anal fins. There is also a lateral row between the rows of bell-shaped organs. The two suborbital photophores (Plate 2) are special types, the more an

THE genus Bathylaco was first established by Goode and Bean (1895: 57) on the basis of a single mature, but rather damaged specimen placed by them in the family Synodontidae. Good and Bean's original classification of the genus has been followed in all subsequent references to their species down to the present time (as by Jordan, Evermann and Clark, 1930: 164), apparently without re-examination of the type. A much smaller, probably immature specimen of a closely related, perhaps identical form was described by Beebe (1933a: 161) as Macromastax gymnos, a new genus and species of the family Alepocephalidae. A second fully grown example of Goode and Bean's Bathylaco nigricans was found among the undetermined alepocephalids of the "Dana" collections sent to the writer for study and identification. The striking similarity to the Synodontidae, and the even greater resemblance to some of the larger myctophids (especially of the genera Serpa and Lampadena) that caused the genus Bathylaco to be placed among the Iniomi, are clearly shown in Figure 1. But the features by which Bathylaco differs from the Iniomi and approaches the Isospondyli seem basically more significant. Until more satisfactory material of these interesting intermediate forms is obtained, and our knowledge of the morphology of the Isospondyli, particularly the Alepocephalidae, becomes more adequate, the new family Bathylaconidae is tentatively placed among the Isospondyli in spite of rather strong, but unfortunately incomplete, indications that a new order, which might be called the Bathylaconi, would be more appropriate. The deficiencies of the material will be fully described under the species. At this point I shall merely discuss the significance of the features which can be observed or reasonably inferred from the available evidence. Functionally, the morphology of Bathylaco is obviously in much better accord with that of the Synodontidae than with any deep-sea isospondylid. The structure of the upper jaws is of particular interest, in that it represents a striking case of evolutionary convergence of heterologous parts. In Bathylaco, as in Synodus, Saurida and in many other Iniomi, the upper margin of the mouth, which is tooth-bearing throughout its length, is formed by a long, straight and rather narrow, but thickened and very strong bone, with a straight, or gently concave ventral profile. Except at the anterior end, it is hard to distinguish this jawbone of Bathylaco from the jawbones of similar Iniomi. But in the Iniomi it is the premaxillaries that form this bone; while the maxillaries are excluded from the margin of the mouth and are generally modified into a semi-hollow sheet, closely applied to the premaxillaries in the genera in which the jaws and the gape take the form here described. In Bathylaco it is the maxillary that has developed the functional form of the premaxillaries of the Synodontidae, with the premaxillaries