26 ARKIV FÖR ZOOLOGI. BAND 14. N:0 18. 



cells which open in this penis canal without any dilatation 

 of the canal. As the secretion products of these prostatic 

 gland cells are very feebly stainable, their presence is rather 

 härd to detect when using low power lenses of the micro- 

 scope. Their staining ability agrees fairly well with t hat of 

 the musculation of the penis. I have had an opportunity 

 to describe similar granular cells emptying their secretion 

 products in the ejaculatory duct of Cryptocelis Ijimai Bock 

 (Bock, 1922). The presence of these granular gland cells is 

 also easily overlooked on account of another kind of gland 

 cells which are so much more conspicuous. There are, namely, 

 intensely stainable basophilous gland cells accumulated in 

 great masses at the basis of the penis and around the f rontal 

 end of the seminal vesicle (Plate I, fig. 5). The ductules of 

 these glands open in the basal two-thirds of the penis canal. 

 I was from the first convinced that the task of these baso- 

 philous secretion products was to form the spermatophores 

 and I was fortunate enough to find my view supported so 

 far in finding great spermatophores injected in the body 

 tissues of another specimen cut in sections (Plate II, fig. 3). 

 Most cotylean polyclads possess an armed penis and with 

 the help of the rigid penis stylet they inject their masses of 

 sperma in the body tissues of other specimens. Spermato- 

 phores were hitherto unknown for the Cotylea, as was also 

 basophilous secretion in connection with the male apparatus. 

 The presence of these spermatophores will explain wby the 

 penis of Amyella is unarmed, so large, and provided with 

 such a wide canal. The stout muscular penis can bring about 

 the injection of the sperma in the body tissue by means of 

 these spermatophores. The spermatophore capsules were 

 stained exactly in the same way as the secretion of the last- 

 mentioned glands. Of course there might remain some slight 

 doubts that the observed spermatophores were not to be 

 attributed to Amyella but, so far as I know, no other polyclad 

 species to which they could be attributed lived in the local- 

 ities for Amyella which I had reason to visit very frequently. 

 It is perhaps superfluous to mention that the spermatozoa 

 were quite typical for a polyclad. 



As mentioned above, the granular gland-cells open in 

 the penis canal. According to my opinion a part of that 

 canal corresponds to the prostatic vesicle of other cotylean 



