CYTOPLASMIC INCLUSIONS OF THE GERM-CELLS 267 
we examine his figures (29), we find, as has already been 
mentioned, that Retzius has represented in many mammalian 
spermatozoa a small bead of protoplasm on some part of the 
middle-piece. In our Text-fig. 1 are reproduced six of this 
observer’s figures, showing at x the bead of the middle-piece. 
Text-FIG. 1. 
i 
WY 
NI 
Ripe spermatozoa after Retzius (29). A=pig. B=sheep. 
c=rabbit. p= cat. E=lemur. F= hedgehog; showing at x the 
protoplasmic bead associated with the middle-piece. 
In fig. 1, a is the spermatozoon of the pig; fig. B that of the 
sheep; fig. c, the rabbit; fig. p, the cat; fig. u, the lemur 
(Lemur catta); and fig. r, the hedgehog. A glance through 
the work of Retzius shows that this peculiar bead has been 
figured by him in several other mammals, namely: Sciurus 
