138 A HISTORY OF RECENT CRUSTACEA 
of feeding, motion, and generation, and in the fabric of the 
trunk within. The vulve are not in the trunk, but in the 
bases of the third pair of legs. The sternum is deeply ex- 
cised between the last pair of legs; the turkish saddle? 
and median apodeme are wanting; the transverse septum 
of the apodemes forms in the middle a central yoke and 
central canal. Further, they show a peculiar affinity to 
Homola by the eye-stalks, which are very long, thin, 
apically inflated, as good as free,” by the first antenne not 
retractile into fossettes, by the first and third maxillipeds, 
which so agree in the two genera that they can scarcely 
be distinguished. With the Maiacea, therefore, Latreilliu 
cannot be confounded, although the form of the trunk is 
triangular, the legs are very slender, the epistome is qua- 
drate, and of the branchiz there are ten pairs, of which 
three are connected with the maxillipeds, two with the 
chelipeds, and three with the following legs, but the last 
united with the penultimate legs.’ 
Latreillopsis, Henderson, 1888, with a type species, 
Latreillopsis bispinosa, from the Philippine Islands, ‘ occu- 
pies an intermediate position between the genera Homola 
and Latreillia. From Homola it is distinguished by the 
arrangement of the rostrum and supraorbital spines, the 
greater length of the ocular peduncles, and more especially 
by the elongated cylindrical legs. In Latreillia, on the 
other hand, the frontal region is narrow and produced so 
as to give the carapace a triangular outline, the supra- 
orbital spines are more strongly developed, and the eye- 
stalks and legs are of greater length.’ It may perhaps be 
regarded as something more than a mere coincidence that 
this link between Homola and Latreillia was obtained by 
the Challenger in one of the two localities in which the 
same vessel took specimens of those two genera. 
Homologénus, A. Milne-Edwards, 1888, bears a name 
altered from the pre-occupied Homolopsis, 1880. It differs 
1 The expression ‘posterior turkish saddle,’ is applied by Milne- 
Edwards to the small arch formed by the sternal apodemes which 
spring from the hind margin of the last segment of the trunk. 
* The Latin is tetis quantis liberis. 
