DEGENERATE (APYRENE) SPERM-EORMATION OE MOTHS. 483 
testes were found full of bundles of botli sorts, apyrene 
and the normal or eupyrene metamorphosing side by side. 
According to Goldschmidt, I suppose the explanation of this 
would be that the haemolympli in early stages favoured the 
formation of apyrenes, but that later in histolysis the fluid of 
the body became adjusted suitably for eupyrenes. Whether 
this explanation can be held good might be proven directly 
by injecting some chemical substances into the pupa, and by 
altering the haemolymph provide an easy basis for com- 
parison with what occurs in the control pupae. 
In molluscs it seems that in such a case as Paludiria, atypic 
spermatozoa arise from ordinary spermatids, but in Strombus 
Reinke traces the apyrenes from special cells not to be 
identified as normal spermatogonia. How could Goldschmidt’s 
explanation apply to either cass in molluscs ? I believe the 
example of the moth testis, where both sorts of sperm ato,- 
genesis goes on side by side is distinctly comparable to that 
of the molluscs. Why does not the chemical unsuitability of 
the hamiolymph apply alike to all spermatid bundles ? 
In connection with these cases of remarkable dimorphism in 
spermatozoa, due to degeneration, the noteworthy case of 
Nerilla should be mentioned (Goodrich ( 8 )). In this archi- 
annelid the male has three genital segments : the first of 
these, the seventh, alone produces normal spermatozoa, but the 
eighth and ninth give rise to curious cells with granules; 
the exact category under which these cells should be 
placed, whether spermatogonia, spermatocytes, etc., and the 
manner in which the granules appear have not yet been 
elucidated, but there can be little doubt that the conditions 
leading to abortive spermatozoa in segments eight and nine 
are to be identified with the same forces which cause the 
apyrene sperm of moths to appear. 
Reinke (1) has some interesting suggestions to make 
regarding the apyrene spermatozoa of Strombus. He says : 
“ (a) They may serve as nurse-cells to the eupyrene spermatozoa 
after copulation and before the latter reach the seminal 
receptacle ; ( b ) they may, by liberation of some substance, 
