REPORT ON THE ISOPODA. 71 



The first maxiUce are sliort and rather beut, and resemble those of Serolis pallida. 



Thoracio Appendages. — The maxiUlpedes (PI. VI. fig. 6) closely resemble those of 

 Serolis pallida and the other Australian species, but are not sculptured like those of the 

 former; tlie lamina terminates on the inner side in the usual way; on the outer side it is 

 produced into a rounded prominence, which extends some way beyond the notch on the 

 inner side; just behind the articulation of the palp is a broad ridge as in Serolis pallida ; 

 the anterior margin of the stipes is crenate; the second joint of the palp is not so distinctly 

 cordate in shape as in many species, and resembles in this particular the other allied 

 Australian forms. 



The thoracic appendages are furnished with two kinds of spines — (1) short broad 

 serrated spines like those of Serolis schi/thei and many other species, (2) longer and more 

 delicate spines, which are somewhat thicker on the outer edge than on the inner; the 

 extremities are bent inwards; these spines seem only to be found on the appendages of 

 the Australian species. The proximal joint of all the ambulatory limbs has a number of 

 fine branched hairs on the inner surface like those of Serolis necera and other species; the 

 second joint is a little shorter, and has one long hair on the inner side just before its 

 articulation with the succeeding joint; the third, fourth, and fifth joints are short, but 

 increase in length up to the fifth. One of the thoracic appendages is shown in fig. 8 ; the 

 others are similar except that the three penultimate joints increase in length in the 

 posterior limbs; in the appendage figured it will be seen that the spines on the outer 

 side arise from step-like processes, on the three penultimate joints the number of these 

 steps gradually increases in the posterior appendages. In the male the second thoracic 

 apjjendage, as in aU other species, is modified into a prehensile organ ; the penultimate 

 joint is rather more elongated than usual, and its two sides are almost parallel ; on 

 the inner surface I counted in one specimen nine of the hairs peculiar to this joint. 



The first three pairs of abdominal appendages have no hairs upon the basal joint, 

 and the two sides of this joint are nearly parallel owing to the absence of the inner 

 projecting angle. 



Station 162, April 2, 1874; lat. 39' 10' 30" S., long. 146° 37' E.; 38 fathoms; 

 bottom, sand and shells. 



13. Serolis elongata, F. E. B. 



Serolis alungata, F. E. BedJari.1, Proc. Zool Soc. Loud., 1884, pt. iii. p. 335. 



Although I have been able to examine only a single female example of this species, 

 its characters appear to me to be sufticiently diflerent to retain it as a distinct species. 



The specimen is a female with fully developed ovigerous lamellae ; its greatest length is 

 10 mm., its greatest breadth Q'b mm. It is most nearly allied to Serolis australiensis. 

 from which, however, it difiers in several respects. 



