Comparative studies in crustacean spermatogenesis

Abstract

This study was undertaken in order to determine how far typea of the class Crustacea, showing in the adult condition well marked iiiorphological differences, mould also present in the derelopnient of the germ-cells characteristic dissimilarity.Accordingly, an examination mas made of the following forms : the Aiiiphipod, Talorchcstia longicoriiis, the Isopods, Oniscus asellus L i m .aiyl Idotea irrorata, tlie Decapods, Hippa talpoides, Astacus fluriatilis and Honiarus rulgaris.There is much variety among the Crustacea with regard to the appearance of the spermatozoa and an increasing complexity of structure from the lower to the highey forms.A coniparison of the spermatozoa makes, therefore, a convenient beginning for a study of this nature. SPERMATOZOA.E:lito:ltioslr.uca.I'hyllopoda.Zacharias (1SO3) has studied the spermatozoa of the Daphnid Polyplieinus.They are amoeboid in shape, the character of the pseudopodia varying with the nature and density of the solution in which they are placed.I n a cell so simple, of coime no distiiictioii can be made between head, middlepiece arid tail.(Text Fig. 1.)I n the spermatozoa of Lepas anatifera L. and Balanus improvisns Darw.Ballowitz (190s) mas unable to discorer any part taking the characteristic nuclear stain of alum carmine.The cell by teasing, however, could be separated into fibrils oiie of Cirripedia.