442 Dr. W. T. Caiman on the Genus Puerulus and the 



instead of cylindrical form. In 1894 the same author* added 

 a third species, P. spiniger, from Amboina, and in 1897 he 

 replaced the preoccupied name Puer by Puerulus f. In 

 1905 Bouvier, overlooking the change in the generic name, 

 described a species, Puer atlayiticus, from the Cape Verde 

 Islands J and Dahomey §. Judging from the very brief 

 description of Bouvier's species, I suspect that it will prove to 

 be identical with Panulirus tnermi's, described by Pocock || 

 from Fernando Noronha, of which the type is in the 

 British Museum. 



Among these species, the first-named, P. angulatus, stands 

 apart. Although the type specimen described by Spence 

 Bate^ was only 36 mm. in length of body and was obviously 

 immature, Alcock ** has since described specimens measuring 

 up to 169 mm. in length, and showing in the males the 

 orifices of the genital ducts. In a female specimen, 164 mm. 

 in length, for which I am indebted to Dr. N. Annandale, 

 Superintendent of the Indian Museum, Calcutta, the orifices 

 of the oviducts are distinctly visible. There can be no doubt 

 that these specimens are adult or nearly so, and thatP. a«^«- 

 latus is a perfectly distinct and independent species, which 

 may be taken as tlie type of the genus Puerulus. Alcock, it 

 is true, ignores the genus altogether, and retains the species 

 in the genus Panulirus. It appears to me, however, that 

 Puerulus, as represented by this species, may well stand as a 

 valid genus, which is probably more closely allied to Linu- 

 parus than to Panulirus. It resembles Linuparus not only 

 in the prismatic form ot the carapace, but also in the dispo- 

 sition of the pleopods in tlie female sex ; in Puerulus and 

 Linu2)arus the pleopods of the second abdominal somite of 

 the female resemble those of the three following somites, 

 having the endopodite narrow and the appendix interna large ; 

 in Panulirus J as in Palinurus and Jasus, the pleopods of the 

 second somite differ greatly from tlie succeeding pairs, having 

 the endopodite broad and foliaceous like the exopodite, and 

 the appendix interna reduced to a vestige ff- 



* Semon"s " Forschungsreisen,'' v. (Deukschr. Med. Nat. Ges. Jena, 

 viii.) p. 19 (1894). 



t Amer. Joimi. Sci. (4) iv. p. 290. footnote (1897). 



X Bull. Mus. Oceanogr. Monaco, xxviii. p. 2 (1905). 



§ Oj). cit. xxix. p. 6 (1905). 



II Journ. Linn. Soc, Zool. xx. p. 516 (1890). 



f ' Challenger' Macrura Rep. p. 81 (1888). 

 ** Cat. Indian Deep-sea Macrura and Anomala, p. 185 (1901). 

 ft I niay take this opportunity of correcting an error in my recently 

 publifehed volume on Crustacea in Sir Ray Lankester's ' Treatise on 

 Zoology.' Ou p. 312 the Scyllaridea are defined (following most recent 



