6i 



be wished, since both the specimens in the collection were mounted in Canada balsam on a 

 glass slide, and in such a position as not to admit of examining all the parts satisfactorily". 

 In 1907 I dissolved the balsam, compared his animals with my drawings of the two species 

 taken by the "Siboga" and arrived at the result, that the specimens referred here to P.pusilla 

 agree well with the types of Sars. 



Dist r i b u t i on. The specimens described by Sars were taken in the Celebes Sea, 



lat.5°44'N., long. i23°34'E., October 22, 1874. The Copenhagen Museum possesses iospecimens 

 captured in the Bay of Bengal by the Danish "Galathea" Expedition, December 20, 1845. 



33. (?) Pseitdanchialiiia inermis Illig. PI. IX, figs. 2 a — 2(1. 



1906. Chlamydopleon inerme Illig, Zool. Anz. B. XXX, N° 7, p. 209. Fig. 16. (Probably). 



Stat. 282. January 15/17. Lat. 8° 25.2 S., long. i27°i8'.4E. Anchorage between Nusa Besi 

 and the N.E.-point of Timor. 27 — 54 m. Plankton, surface. 4 specimens, all males. 



It may be inserted here, that the Copenhagen Museum possesses a female with the 

 marsupium well developed taken in the Bay of Bengal, lat. 6°22 / N., long. 95°54'E., "Galathea" 

 Expedition. 



Description. — This species is so closely allied to P. pusilla that it may be sufficiënt 

 to enumerate the differences. The frontal plate is in the male (fig. 2 a) somewhat, in the female 

 considerably, narrower than in P. pusilla. The eyes of the males are a good deal larger than 

 in the preceding species, the last joint of the eye-stalks not cylindrical but increasing conspi- 

 cuously in breadth outwards and much broader than long; the single eye preserved in my single 

 female is a little smaller than in the male, yet a little larger than in the preceding species, 

 and the eye-stalk increases in breadth outwards. First abdominal segment in the female with 

 free lateral wings which are shaped nearly as in Anchialina grosso, with the exception, that while 

 the wing is directed obliquely backwards in the latter species, it is directed obliquely forvvards 

 in P. inermis. The male pleopods nearly as in the preceding species, but the endopods in 

 second and third pairs are still a little shorter and smaller. Telson (figs. 2 c and 2 cl) a little 

 more than three times as long as broad and at the middle half as broad as at the base, with 

 5, in the single female 4, pairs of lateral spines. 



Length of a male 2.9 mm., of the female 3.2 mm. 



Remarks. — ■ Illig's preliminary figures differ from my animals in showing the frontal 

 plate broader, the eyes proportionately somewhat smaller, the endopod of the uropods narrower 

 and the telson a little shorter than in my specimens, but I suppose that these differences may 

 be due to minor inaccuracies or partly to some variation, thinking that the fact that his animals 

 have 5 pairs of lateral spines on the telson, may be a sufficiënt ground for referring my specimens 

 to his species. 



Distri bution. — Above is stated that the Copenhagen Museum possesses a specimen 

 from the Bay of Bengal: lat. 6°2 2'N., long. 95°54'E. Illig's specimens were taken by the 

 "Valdivia" East of Ceylon and in the " Mentaweibecken". 



