tege Mineralogy. 871 
ical nozzle or penis-like organ. This organ fits exactly into the begin- 
ning of a long groove that extends along the first pleopod. The tip of 
this appendage is sharp and hard and is seen to actually penetrate into 
the cavity of the annulus. The sperm that issues from the vas deferens 
passes along the groove of the first pleopod to its tip and so into the 
annulus. 
The second pleopod piays some part in the process of transfer, but 
this is known only by inference, not by direct observation. It has a 
peculiar triangular spoon at its end which is held applied to the first 
pleopod and it also has a terminal filament that fits nicely into the 
groove at the tip of the first pleopod. It may easily act to shove the 
sperm masses down along the groove of the first pleopod as well as to 
protect them from contact with the water and from going astray (which 
rarely happens.) 
Apparently both sides of the body are active in this sperm transfer, 
but this is not certain. 
The process of sperm transfer continues, with interruptions, for sev- 
eral hours, and then the male separates from the female. He first 
moves backward, and rising places the crossed leg back again into its 
normal position, and then releases the female. 
During the entire conjugation the male is obviously excited as is 
shown by the vibrations of the anterior maxillipedes and by the very 
strong current of water cast out from the gill chamber by the exhalent 
apparatus. The female, on the contrary, is remarkably inert and shows 
no sign of any activity even in the respiratory organs. At times there 
is, however, a slight convulsive twitching of the base of the abdomen, 
possibly connected with sensations during sperm transfer. 
The eye-stalks were also seen to move when disturbed by the claws 
of the male. 
In two instances the dexterity and skill of the male were well shown 
after the first stages of grasping the female had been imperfectly ac- 
complished. In these cases the male mounted upon the dorsal surface 
of the female and seized her claws with his, having failed to turn her 
over in proper sequence. In this unusual position the male attempted 
to adjust his appendages to the female and then became aware of the 
fact that the conditions were unusual. The male depressed the first an- 
tennz so that they were firmly applied to the dorsal surface of the 
thorax of the female and bent forward by the pressure. The sensation 
so obtained seemed to initiate the almost intelligent action that followed. 
In one case the exopodites of the third maxillipede were also used in 
feeling the female. In about ten minutes the male turned the female 
