167 



6. Heterocarpus ensifer A. M.-Edw. var. parvispina de Man. PI. XIV, Fig. 41 — \\b. 



Heterocarpus ensifer A. M.-Edw. var. parvispina J. G. de Man, in: Zoolog. Mededeelingen, 

 uitgegeven vanwege 's Rijks Museum van Natuurlijke Historie te Leiden. Deel III, Afl. 4, 

 December 1917, p. 282. 



For the typical species confer : 



Heterocarpus ensifer A. Milne-Edwards, in: Annal. Scienc. Nat. (6) XI, 1881, Art. N" 4, p. 8 



and Recueil de Figures de Crustacés nouveaux ou peu connus, Avril 1883, PI. 32. 

 Heterocarpus ensifer C. Spence Bate, Report Challenger Macrura, 1888, p. 638, PI. CXII, fig. 4. 

 Heterocarpus ensifer W. Faxon, in: Buil. Mus. Comp. Zoology, Cambridge 1896, p. 161. 

 Heterocarpus ensifer L. A. Borradaile, in : A. WlLLEV's Zoological Results. Part IV, Cambridge 



1899, p. 413. 

 Heterocarpus ensifer M. J. Rathbun, in: U.S. Fish Commission Bulletin for 1903, Part III, 



Wash. 1906, p. 917, PI. XXI, fig. 7. 

 Heterocarpus ensifer H. Balss, Ostasiatische Decapoden II, München 19 14, p. 37. 

 Pandalus carinatus S. I. Smith, Buil. Mus. Comp. Zoology, Vol. X, N° 1, Cambridge, 1882, 



p. 63, PI. X, figs. 2—2/, PI. XI, figs. 1—3. 



Stat. 38. April 1. 7°35'.4S., U7°28'.6E. Bali Sea. 521 m. Bottom coral. 1 young specimen. 

 Stat. 105. july 4. 6°8'N., 121° 19' E. North of Sulu-island. 275 m. Coralbottom. 2 young 



specimens. 

 Stat. 254. Dec. 10. 5°4o' S., i32°2Ó'E. Off the Kei-islands. 310 m. Bottom fine grey mud. 



2 adult males. 



Heterocarpus ensifer A. M.-Edw., the hrst described species of this genus, differs from 

 Heteroc. Sibogae de Man, with which it has hitherto been confounded, by the following. The 

 carapace appears a little less high with regard to its length than in Heteroc. Sibogae: the 

 carapace of the larger male from Stat. 254 is 24 mm. long and 17 mm. high, in a specimen 

 of Heteroc. Sibogae from Stat. 74, however, these numbers are 26 mm. and 20,5 mm. The first 

 tooth of the postrostral crest is constantly placed a little anterior to the middle of the 

 carapace, in Heteroc. Sibogae, however, always d i s t i n c 1 1 y b e h i n d the middle. Posterior to 

 the first tooth the crest runs straight backward, but appears more or less distinctly angular in 

 Heteroc. Sibogae. The i st and the 2 nd abdominal terga are not carinate, while in Heteroc. Sibogae 

 both terga are provided with a high, prominent and sharp carina. In full-grown 

 specimens, however, like in the two males from Stat. 254, the i st tergum does not appear 

 regularly rounded, vvhen looked at from behind, but slightly angular, the angle, 

 however, is rounded and smooth. On the 2 nd tergum this angle is hardly visible, so 

 that this tergum appears almost regularly rounded. 



Figures of Heteroc. ensifer A. M.-Edw. have been published by A. Milne-Edwards, 

 Spence Bate and Miss Rathbun (locis citatis), but in all these figures the spine, into which 

 the carina of the 4 th tergum is produced, appears but little shorter than the spine of the 3 rd . 

 In the five specimens, however, that were collected by the "Siboga", the spine of the 4 th tergum 

 is considerably smaller than that of the 3 vd , its length being only one-fourth the length 

 of the latter, when measured from the posterior margin of the somites: it is only on account 

 of this dirïerence that these specimens are regarded as a distinct variety. Spence Bate (1. c. 

 p. 639) remarks about the two males, trawled by the "Challenger" between the Philippine 

 Islands and Borneo, that the spine of the fourth tergum, "is not quite so large as that on the 



