468 Mr. G. W. Smith. On the Anaspidide and [June 10, 
The alimentary canal is furnished with a gastric mill of a simple character, 
provided with numerous ridges and sete; behind the stomach enter about 
thirty long, slender, and unbranched ceeca of a glandular nature (“liver”). 
In the abdominal region, two dorsal unpaired cceca of a small size are 
present, which are difficult to compare with similar structures in the 
Decapoda, owing to the backward position of the anteriorly placed ccecum. 
The whole structure of the alimentary canal is peculiar, and not quite like 
that of any other group of the Crustacea. 
The ovaries and testes are paired tubes stretching the whole length of the 
body. Their ducts are simple tubes not provided with accessory glands. 
The adult spermatozoa are filiform, with globular heads and an elongated 
flagellum, an important diagnostic character shared in common with the 
Mysidacea. 
The excretory glands are large coiled tubes ending in an expanded sac and 
opening at the bases of the second maxilla. No antennary glands are 
present. | 
The presence of maxillary glands, which are characteristic of the 
Entomostraca, must be looked upon as a primitive character; but it occurs 
in a few instances among the Isopoda as well. The nerve-cord consists of 
eight free thoracic ganglia, corresponding to the eight free thoracic segments, 
and six abdominal ganglia. The definite discovery that there is a free thoracic 
ganglion corresponding to the first thoracic segment is of some importance, 
since doubt has been thrown upon the real segmental value of this segment, 
which in all other Malacostraca is definitely fused with the head. 
Breeding Habits.—Since there is no trace of a brood pouch, it was of interest 
to establish what the female does with her eggs, especially as this is a 
character of great taxonomic importance. The male deposits two very large 
spermatophors in the spermatheca of the female; these spermatophors are 
curved structures, and project outside the spermatheca. The spermatozoa 
pass into the spermatheca, and the spermatophors drop off. The eggs, which 
are pale purple in colour and measure about a millimetre in diameter, are 
passed out of the oviducts, and probably are fertilised as they pass out by 
spermatozoa, which migrate from the spermatheca, and possibly they are 
assisted in this migration by the setose projections on the internal faces of 
the coxopodites of the last three pairs of thoracic appendages, these 
projections being a sexual character confined to the female. 
The female deposits and hides her eggs singly, and not agglutinated 
together, under stones and among the roots of water plants, being the only 
crustacean with the exception of the peculiar parasitic Argulidée to do this.* 
* Certain Euphausiide also deposit their eggs, but not the family as a whole. 
