8 STOLICZKA :— TERTIARY 



Family,— CANCEBID^. 

 (ye*iM5,— PAL^OOARPILIUS, Milne-Ed. 



Hist. Crust. Podophthalmaires foss. par Al. M.-Ed wards, 1865, vol. I, p. 183. 



Al. Milne-Edwards proposed the above generic name for a certain number of 

 tertiary and other canc:eridjb, formerly referred to Cancer, and then to Atergatis. 

 He very properly pointed out the greater generic relation of those species to Car- 

 pilius than to Atergatis, considering Desmarest's Cancer macrocheilus as the type 

 of the new genus JPalceocarpilius. 



In summing up the principal characteristics of the genus, as distinguished 

 from its ally Carpilius, M. -Edwards says, — "nous pouvons placer en premiere ligne 

 la presence des tubercules sur le hord supirieur de la m^in et swr la face externe 

 de Vavant bras, la longueur extreme de V article hasilaire des antennes externes" 8fc. 

 Now, the really important character appears to me to consist only in the great 

 length of the basilary joint of the antennae ; the presence or absence of tubercles 

 on the hand cannot be included in the generic characters. The median extension 

 of the front edge seems, however, to be a very characteristic point in the shape of 

 the carapace of Falceocarpilius. 



In the description of the genus, Milne-Edwards also says that the ambulatory 

 feet are cylindrical, as in Carpilius, and that in the male the tail consists of six 

 joints, the fourth and fifth being united. I do not think that these characters 

 could strictly be applied to the species of Falceocarpilius in general. First, the 

 ambulatory feet are never, strictly speaking, cylindrical, not even in Carpilius; 

 they are always a little compressed, but with the upper and lower edges rounded, 

 not crested as in Atergatis. In specimens of the Indian Fal. rugifer, the third, 

 fourth and fifth joints are united in the tail of the male, and this appears rather 

 the rule than the exception. In Milne-Edwards' figure la, pi. iii (1. cit.) of 

 F. macrocheilus, those three joints also appear to be united ; and Reuss indicates 

 their form merely by a punctated line, not by a distinct suture as between the other 

 joints. (Compare Denksch Akad., "Wien, vol. XVII, pt. I, pi. xii, fig. 2). 



Pal^ocakpilitts bugifeb, Btol., PI. IV, Pigs. 1 — 6, and Pi. V, Eigs. 1 — 5. 



Carapace transversally ovate, the breadth exceeding the length very nearly 

 by one-third, or being in proportion to each other as 100 : 68 or 69 ; very convex, 

 the front being in young specimens almost perpendicularly deflected; in older 

 specimens, the deflection is sometimes a little less pi-ecipitous. The fresh surface is 

 covered with larger and smaller round, shallow, pits, and about the branchial regions, 

 with very conspicuous, more or less confluent, transverse rugosities. In old speci- 

 mens, these rugosities sometimes also extend over the greater part of the median 

 gastric region. On the posterior slope and at the postero-lateral margin, as well as 

 at the lower side, the surface is smooth ; but when the outer somewhat glazy laver 

 is removed, the entire surface becomes equally and densely granular, and by further 



