A REVIEW OF THE MYSIDACEA 63 



5596, 1 male, 1 female. China Sea : Vicinity of Formosa, Albatross 

 station 5320, 1 female. 



Distribution.— Waters of the Dutch East Indies (Hansen, 1910) ; 

 India (Tattersall, 1922) ; Arabian Sea (Colosi, 1924) ; Hong Kong and 

 Peru ( Coif mann, 1937) ; Queensland and the Barrier Keef (Tattersall, 

 1928 and 1936b), and the Philippine Islands. It is thus an abundant 

 species in the tropical waters of the western Pacific and Indian Oceans. 

 It is an inshore form, always taken near land, never oceanic. Coif- 

 mann's record of this species from Peru is somewhat surprising. The 

 records for the stations given under "Occurrence" are interesting as 

 showing the abundance of this species at the surface during hours of 

 darkness. 



Remarks. — Breeding appears to go on all the year around in the 

 waters of the Philippine Islands. Practically all the above records 

 include breeding females. Several specimens were infested with a 

 dajid parasite, which appears to me to be very close to, if not actually, 

 Dajus siriellae G. O. Sars. 



Dana (1852b, p. 569), records a specimen of Siriella that resembled 

 S. gracilis but that had a prominent tooth or spine on the lower side 

 of the sixth abdominal segment, a character not observed in S. gracilis. 

 Czerniavsky (1882a) named this specimen S. suluensis. The species 

 has not since been seen. I suggest that S. suluensis is the same as S. 

 vulgaris Hansen, though I am unable to suggest what the spine noted 

 by Dana really is. The two species are otherwise very similar. 



SIRIELLA VULGARIS ROSTRATA, new variety 

 FlGUEE 14 



Description. — The specimens here recorded agree very closely in 

 all their characters with Hansen's description of S. vulgaris except 

 that the rostal plate (fig. 14, a) is very much longer, acutely produced 

 into a long spiniform rostrum which extends forward just beyond 

 the cornea of the eyes. In S. vulgaris the rostral plate is short, acute, 

 and extends forward only to the base of the eye stalks. The close 

 resemblance in all the other characters leads me to regard these 

 specimens as only a variety of the typical form. I give herewith 

 figures of the main appendages of the variety for comparison with 

 those of the type (figs. 14, a-f). 



Type lot.— U.S.N.M. No. 81254, from Arno Atoll, Marshall Islands. 



Occurrence. — Several hundreds of specimens of both sexes were 

 taken by the Albatross by electric light at the surface of a lagoon, 

 January 24-26, 1900, at the type locality. The Albatross likewise 

 took 3 males and 2 females at Kusac, Caroline Islands, electric light, 

 surface, February 7, 1900. Philippine Islands : Albatross, Bagacay 



