464 Records of the Indian Museum. [Voi,. XXIV, 



uropods. It is distinguished from E. minuta in having the outer 

 margin of the antennal scale smooth and not serrate, as well as in 

 having an extra pair of spines on the telson. 



Genus Hypererythrops Holt and Tattersall. 



Hypererythrops spinifera (Hansen). 



Text-figs. na-i. 



Erythrops spinifera, Hansen, 1910, p. 62, pi. 9, figs. ^a-c. 

 Locality . — Port Blair, Andaman Islands. 

 St. 3. Two males, two females. 

 St. 19. Six males, eight females. 



Remarks. — These specimens agree very closely with Hansen's 

 description and figures of Erythrops spinifera except in one point, 

 the number of spines on. the lateral margins of the telson. Han- 

 sen gives the number as 10-13 and his figure shows them to be 

 arranged at practically regular intervals along the whole margin. 

 In these specimens I find the spines to be fewer and to be more 

 distantly and more irregularly arranged. The figure (text-fig. nh) 

 shows a typical telson among the Port Blair specimens. But 

 the spines on the telson appear to be very variable in number and 

 seldom the same number on both sides of a single telson. The 

 smallest number of spines on each margin is five and the largest 

 number nine. In only four specimens was the number of spines 

 on each side of the telson the same and frequently the two sides 

 differed by two spines. 



The apex of the telson in the Port Blair specimens bears two 

 pairs of long stout spines, the inner pair of which is always 

 longer than the outer pair but the proportion between the lengths 

 of the outer and inner spines varies considerably, in some specimens 

 approaching the condition as figured by Hansen in which the two 

 pairs are nearly equal in size, in other specimens having the pro- 

 portions shown in my figure in which the outer pair is considerably 

 shorter than the inner pair. Between the latter are a pair of quite 

 small spines and a pair of long plumose setae. Hansen found the 

 setae only in one of his specimens and the spines only in the 

 other. 



In other respects these specimens agree so closely with Han- 

 sens's species that I feel that they cannot be considered as more 

 than a variety, especially in view of the great variation which they 

 show among themselves. I am content, therefore, to record them 

 under Hansen's name, to point out the differences I have found 

 and to figure the more essential parts for comparison. 



Hansen had no mature males at his disposal. The Port Blair 

 specimens include several males and an examination of them shows 

 that the species must be referred to the genus Hypererythrops Holt 

 and Tattersall (1905). This genus differs from Erythrops in having 

 the telson much longer in shape with its lateral margins armed 



