186 Records of the Indian Museum. [Vol. XXIV, 



sufficient to account for all or nearly all the differences he has 

 noted. The descriptions themselves do not indicate other fea- 

 turesof any importance and it is clear that if Nobili's aberrans, 

 I,enz's latirostris and Miss Rathbun's hermitensis are to be re- 

 tained as distinct, it must be by reason of fresh and hitherto undis- 

 closed characters. 



While in Paris in 1920 I was unable to examine the type of 

 Nobili's Palaenionella aberrans from Djibouti, as the specimen had 

 unfortunately been mislaid; but, through the courtesy of Prof. 

 Ch. Gravier, I was able to see the female from Bahrein I. in the 

 Persian Gulf which Nobili subsequently referred to the same 

 species. In the figure of this specimen (loc. cit., 1906, pi. iv, fig. 9) 

 the dorsal swelling of the carapace is very greatly exaggerated, 

 and the statement that a podobranch occurs on the second maxil- 

 liped is erroneous. 



P. brevicarpalis .in my estimation is a species of very wide 

 distribution, extending from the Red Sea and east coast of Africa 

 to the Santa Cruz Is. in Oceania. I have examined a specimen 

 from the last named locality and have compared examples from 

 the Torres Straits with the series in the Indian Museum collection. 

 I am convinced that all belong to a single species. 



The rostrum varies considerably in length. As - a rule it 

 reaches to or a little beyond the end of the antennular peduncle ; 

 rarely it is shorter, sometimes extending only to the middle of the 

 second peduncular segment. In lateral view it is deep, with convex 

 upper and lower margins and at the apex it is sometimes a trifle 

 upturned. On the upper margin there are from 5 to 7 teeth l 

 usually 6, which are for the most part evenly spaced. In about 

 half the specimens the posterior dorsal tooth is situated a little 

 behind the back of the orbit; in most of the others it is immedi- 

 ately above this point, while very rarely it is placed further forward. 

 The distal upper tooth is not so near to the tip as to give it a bifid 

 appearance. On the lower margin there are 1 or 2 teeth,* nearly 

 always 1 ; these are scarcely smaller than those on the upper mar- 

 gin and are situated in the distal third of the rostral length. Very 

 rarely specimens are found with the lower border unarmed. 



The strong curvature or swelling of the dorsum of the cara- 

 pace is only seen in large females; in males, and in females that 

 are small or of moderate size, there is scarcely an indication of it. 3 



1 Of fifty-one specimens fifteen have 5 dorsal teeth, thirty-two have 6 and 

 four have 7. / 



2 Of fifty-one specimens one has the ventral margin unarmed , forty-six have 

 1 ventral tooth and four have 2 teeth. 



s Only fourteen of the sixty-two specimens in the collection possess this swol- 

 len carapace. That the feature is not shown in Schenkel's figure is sufficiently 

 explained by his statement, — ■' der Cephalothorax war wiees scheint etwas aufge- 

 trieben, namentlich auf der Oberseite ; leider hat er sich, der W'eichheit des Tegu- 

 mentes halber, nicht gut conserviert." In Nobili's figure, as 1 have remarked 

 above the character is greatly exaggerated. 



