322 Memoirs of the Indian Museum. [Vol. V, 



specimens lends support to the view, based on other evidence, that this species at any 

 rate does not breed in the lake. 



In the larger males the great barbed spine at the base of the third legs is well 

 developed. 



It is only in very large individuals that the rostrum has the comparatively 

 straight dorsal outline shown in Alcock's figure In the Chilka specimens, vrhich do 

 not exceed 75 mm. in length, there is a well elevated basal crest reaching from the 

 posterior spine of the dorsal series to a point opposite the extremity of the eyes. 



There can, I think, be no doubt that the specimen from Makassar recorded by de 

 Man as ' Penaeopsis sp.' is to be referred to this species. The figure of the thelycum 

 is an exact representation of that of P. dobsoni ; it is indeed more exact than the 

 figure in Alcock's memoir, the latter suggesting a slight asymmetry which has no 

 actual existence 



In life P. dobsoni is semitransparent ; the pigment spots scattered on the cara- 

 pace and abdomen are for the most part red, but tend to a browner shade on the 

 rostrum and to a greenish tone on the posterior edges of each of the abdominal 

 pleura. The antennules, antennae and antennal scales are dotted with red. There 

 is a double row of reddish spots on the telson, the margins being greenish. Both 

 uropods are red at the tip, the exopod being also bordered with red externally. 



Like P. monoceros, this species is abundant in all parts of the Chilka Lake at all 

 seasons of the year. It is particularly common in the main area on a muddy bottom. 

 It appears to have a more restricted distribution than other species and has been 

 recorded from both sides of the Indian Peninsula and from Makassar. 



I'amily SERGESTIDAE. 



Subfamily LUCIFERINAE. 



Genus LUCIFER, Vaughan Thompson. 



In giving an account of certain pelagic Decapoda collected by Mr. J. Stanley 

 Gardiner', I expressed the opinion that Milne-Edwards' species,!,, reynaudi and L. 

 typus \ could not be recognised with any certainty from the original descriptions and 

 that Dana's work, published in 1852 *, must form the basis of our classification. So 

 far as Milne-Edwards' L. reynaudi is concerned, this view had already been adopted 

 by Faxon in 1895.^ 



Owing to lack of material for comparison, my account of the species represented 

 in Mr. Gardiner's collection contains one serious misstatement. The specimens 

 referred to Dana's L. reynaudi were said to be specifically distinct from others, 

 obtained on the Ceylon coast, that I identified as L. typus, auct. Examination of 



' Kemp, Trans. Linn. Soc, Zool. (2), XVI, p, 57 (1913). 



* Milae-Edwards, Hist. nat. Crust., II p. 469 (1837). 



* Dana, U.S. Explor. Exped., Crust. I, p. 668 (1852J. 



* Faxon, Mem. Mus. Comp. Zool., Harvard, XVIII, p. 214 (1895). 



