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A biography of scientist Gregor Mendel is presented. Born as Johann Mendel on July 22, 1822, at Heinzendorf in Silesia, he entered the monastery to study philosophy where he also took the name Gregor. He then went to the University of Vienna, Austria, in 1851 to study physical and biological sciences. Mendel is remembered for his works on hybridization and plant breedings which established that crossed varieties produced only uniform offspring. He died on January 6, 1884.

Necessity of a thorough study of hybridization, following the breakdown of reproductive isolating mechanisms between naturally occurring populations, has been felt by biologists in general and ichthyologists in particular. In this connection a formula for ‘hybrid index’ developed mainly by Hubbs & Kuronuma (1942) and Hubbs, Hubbs & Johnson (1943) has widely been in use, to test the assumption of hybridity and to study the mode of inheritance. Misra, Bateson & Keenleyside (1970) gave statistical methods of analysing hybrid indices estimated for characters of the ‘continuous’ type, and also provided a numerical example. Recently Misra (1971) gave a method of doing similar analysis for hybrid indices estimated for meristic characters, but no example was provided, as data were not available to him. This paper presents a study of hybridization in the sunfishes (genus Lepomis) of Pinehurst Lake, Ontario, Canada, based on the number of scales below the lateral line; the primary purpose of the study is to show the complete computational procedure involved in the application of the method of Misra (1971), so that those users of the method who are mainly interested in the applied aspects of the method, can bypass the mathematics easily. [ABSTRACT FROM AUTHOR]

The distribution of male and female florets in heads of monoecious populations is represented by a curve joining points on a graph of percentage of female florets against rank in the same percentage. Comparison of curves for samples from different origins in Cotula minor and C. atrata subsp. atrata shows that sex expression is not greatly influenced by macro-environmental differences. Much of the total intra-population variation in sex expression appears in the heads collected at one time from a single plant. The rank-frequency curves show marked differences between species in the percentages of male and female florets. The average percentage of female florets in seventeen monoecious species is negatively correlated with the floret length, a measure of adaptation to out breeding. In three species, the seed set and subsequent germination percentages are slightly lower after self-pollination than after cross-pollination. Self-fertilization probably occurs in varying degrees in the monoecious species. Monoecy has arisen independently in sections Leptinella and Strongylosperma. [ABSTRACT FROM AUTHOR]

A short review is given of the literature on sterile breeding of higher plants. A simple rearing apparatus is described. Instructions are given for its use with special regard as to the cultivation of endospermless wheat, 56 seedlings of which can be cultured in each unit. [ABSTRACT FROM AUTHOR]

The author discusses the effectiveness of breeding program on domesticated animals in response to the preservation on wild life worldwide. He emphasizes that the survival of most endangered species and animals are already critical not only in the country as will as worldwide. He offers various techniques on how to preserve wild life animals such as frozen semen, artificial insemination, superovulation, and embryo transplant. He presents few of the endangered animals that need preservation including Tasmanian wolf, Aribian oryx, Philippine eagle, and Sumatran rhinoceros. He added, that by using the technique, it develop a better breeding program for the preservation of the endangered wild life.