8o 



132 mm., from Stat. 302, the rostrum that reaches straight forward, to just beyond the 

 i^' antennular article, shows distinctly seven teeth; these teeth gradually decrease in size from 

 the 3''' to the 7''' which is very small and rudimentary. The rostrum of 9 females out of the 22 

 that were examined was armed with six teeth in addition to the epigastric tooth ; in 6 females 

 I observed five teeth and finallv there were 4 females with seven and 3 with six teetli, the 

 foremost of which was again rudimentary. The usual number proved therefore to be 

 six, but rost ra with five teeth are not at all rare; in some specimens a seventh 

 resp. a sixth, though rudimentary, tooth occurs. The quite distinct post-rostral carina is not 

 grooved, but carries sometimes one or two shallow pits. 



It is remarkable, indeed, that in Spence Bate's figure of a probably adult female the 

 rostrum appears hardly longer than the i^' antennular article, for among the 22 females collected 

 by the "Siboga" a similar, short rostrum does only occur in two young females from Stat. 312. 



In the adult male the inner flagellum of the upper antennae is lY^ — lYg-times as long 

 as the peduncle, the outer is one-third shorter; the widened and grooved part of the outer 

 flagellum occupies about one-third of its length ; in the adult female the flagella are shorter, 

 the inner being nearly as long as the peduncle. 



The scaphocerite of the outer antennae is, in the male, usually a little shorter, but in 

 the female somewhat longer than the antennular peduncle. Not only the legs of the 5''^ and 

 of the 4"^ pairs, also those of the y^ are devoid of an epipod. 



Parapenaeus jïssurus attains the length of 135 mm. 



General distribution: Philippine Islands (Spence Bate) ; Talili Bay, New Britain 

 (Borradaile) ; Gaujam coast, Gulf of Martaban, Andamans (Alcock). 



33. Parapenae7is Investigatoris Alc. & And. 



Parapenaeus investigatoris A. Alcock and A. R. S. Anderson, Ann. Mag. Nat. Hist. (7) III, 



1S99, p. 279; Illust. Zoology Investigator, Crust. PI. XLI, Fig. i, ia, i/>. 

 Parapenaeus fissiirus A. Alcock and A. R. S. Anderson, Journ. Asiat Soc. Bengal, LXIII, 



Part II, N° 3, 1894, p. 144. (nee Spence Bate). 

 Peneus (Parapeneus) investigatoris A. Alcock, Catal. Indian Deep-Sea Crustacea, Calcutta, 



1901, p. 18. 

 Parapeneus investigatoris A. Alcock, Catal. Indian Decap. Crust. Part III. Macrura. Fase. i. 



Calcutta, 1906, p. 32, PI. VI, Fig. 17 and ija — r. 



Stat. 254. December 10. S°40'S., 132° 26' E. Near Kei-islands. 310 m. Fine, grey mud. i 

 young male. 



The rostrum of this specimen, which is 48 mm. long, is somewhat directed upward and 

 carries 6 teeth besides the epigastric tooth. Measured along the carinate, upper margin the 

 5"' abdominal somite appears to be 4 mm. long, the 6''^ 9 mm. The telson is broken off just 

 beyond the lateral prongs. 



There are n o epipods on the t h r e e last thoracic legs, a fact already mentioned by 

 Alcock and Anderson (1. c. 1894). 



General distribution: Off Pulicat; Gulf of Manar; Andaman Sea, N. E. and N. 

 of North Island (Alcock). 



80 



