I07 



larger, though not yet adult : the largest is io6 mm. long. The rostrum of this female is as 

 long as the antennular peduncle and "-dentate; the i^' tooth is almost twice as far distant 

 from the 2"'^ as the 2°<i from the 3''''. The three other females gradually decrease in size, the 

 formulae of their rostrum are in the two larger 7, in the youngest 7. 



R e m a r k s. Some years ago I have described two females of this species, captured at 

 Amboina by the late Dr. Brock, in which the post-rostral carina was not grooved and in 

 which the first legs were bispinose (in: Archiv. f. Naturg. 53<='' Jahrg. 1888, p. 565). Probably 

 an individual variety. 



General d i s t r i b u t i o n : Fiji Islands (Spence Bate) ; Celebes and Mauritius (H. Milne- 

 Edwards); Gulf of Tedjourah, Red Sea (Nobili). 



48. Penaeus japonicus Sp. Bate. 



Penaeus canaliculatus Oliv., var. japonicus C. Spence Bate, Report Challenger Macrura, 1888, 



p. 245, Pis. XXXI, XXXII, Fig. 4, XXXVII, Fig. 2. 

 Penaeus canaliculatus Oliv., var. japonicus A. Alcock, in : Ann. Mag. Nat. Hist. (7) XVI, 



1905, p. 514. 



Penaeus canaliculatus A. Ortmann, in: Zool. Jahrb. V. Abth. f. Syst. 1890, p. 448, PI. XXXVI, 



Fig. 2a, b. 



Penaeus canaliculatus K. Kishinouye, in: Journal Fisheries Bureau, Vol. VIII, N" i, Tokyo, 



1900, p. 6, II, PI. I and PI. VII, Fig. i, lA— iC. 



Penaeus canaliculatus M. J. Rathbun, in: Proc. U.S. Nat. Mus. XXVI, 1902, p. t,?- 



Penaeus canaliculatus A. Alcock, Catal. Indian Decap. Crust. III. Macrura. Fase. i. Calcutta, 



1906, p. 14, PI. II, Fig. 6a — c. 



Penaeus japonicus G. Nobili, in: Annal. Scienc. Natur. 9e Sér. T. IV, 1906, p. 10. 



Stat. 16. March 15/16. 6°59'S., 11 5° 24'. 7 E. Bay of Kankamaraan, S. coast of Kangeang. 



22 m. Mud. I very young male. 

 Stat. 131. July 24/25. Anchorage off Beo, Karakelang-islands. 13 m. Mud and sand. 2 females. 

 Stat. 296. January 24/26. 10° 14' S., 124° 5'.$ E. Noimini Bay, South coast of Timor. Reef 



I young male. 

 Stat. 323. February 24/25. Sangkapoera-roads, Bawean-island. 12 m. Mud. 2 young males. 

 Postillon-islands. i female presented by Mr. JaCiIUIN of Makassar. 



The specimens are of medium size or very young. 



The male from Stat. 16 is 34,5 mm. long, the youngest of all. The rostrum that reaches 

 to the middle of the penultimate joint of the antennular peduncle, is 7-dentate ; five teeth are 

 on the carapace, the i^' is almost twice as far distant from the 2°'^ as the 2"*^ from the y^. 

 The post-rostral carina is flattened, but not 3-et grooved; the lateral grooves are, however, 

 distinct and extend as far backward as in the adult. Accordinsj to Miss Rathbun, in youno- 

 specimens of the closely related P. viarginaücs Rand., a species that inhabits the coasts of 

 the Hawaiian Islands, the median carina and the lateral grooves fade out before reaching as 

 far back as in the adult. (Vide: U.S. Fish Commission Buil. for 1903, PI. III, Wash. 1906, 

 p. 902). The fourth abdominal somite is still rounded posteriorly. 



The two females from Stat. 131 are of equal size and iiomm. long. The rostrum just 

 as long as the antennular peduncle in one specimen and slightly reaching beyond it in the 

 other, is 7-dentate in the former and 7 in the latter. In both specimens four teeth are on the 



107 



