Morse.] ane [March 19, 
fact that a portion of the pallial membrane separated from the animal, shows 
the circulation going onas usual. The vascular bands are also strongly ciliated, 
and in Terebratulina, as in Lingula, the perivisceral circulation is probably in- 
duced by ciliary action. 
That the accessory vescicles, then, belong to the reproductive system, and not 
to the circulatory system, there can be no doubt, but just what their function 
may be, has yet to be discovered. 
I copy from that inexhaustible work of Claparéde, the Annelids of the 
Gulf of Naples, a figure of the segmental organ of Alciope Cantrainii, and 
accompany it with a figure of the segmental organ of Terebratulina septentri- 
onalis with its accessory vescicle attached in the same position. There is at 
least something suggestive in the relations of the two figures, though by this 
suggestion I would not throw doubt on Claparéde’s determinations. With the 
impression that the sexes were united in Terebratulina, I was inclined to regard 
Fig. 30. 
: = Qy UZ 
Segmental organ of Terebratulina. 
s. segmental organ. m. inner 
mouth of ditto. o. external ori- 
fice of ditto. g. genital band. a. 
accessory vescicle. 7. intestine. 
*.0 
Segmental organ of Al- 
ciope Cantrainii. m. inner 
mouth of segmental organ. 
o. external orifice of ditto. 
t. testes. 
the external parietal glands discovered by me as representing the testes. With 
the identification of the spermaries as above described, and the consequent sep- 
aration of the sexes, we must seek for another interpretation of the glands. 
As they are extremely mucous, and intimately surround the external tub- 
ular orifices of the segmental organs, the egg cannot possibly escape with- 
out first coming in contact with whatever substance these glands may 
secrete, and it is highly probable that they are instrumental in investing 
the egg with some external coat. The glands are very white in color, and are 
filled with minute granules which I at first mistook for spermatozoa. It is inter- 
esting to observe that they are present in both sexes, but what service they do in 
the male it is impossible to conjecture. 
