REPORT ON THE ISOPODA. 85 



which cover the rest of the palp. This is represented in PL HI. tig. 10, a, which is drawn 

 from the maxillipede of the right side of Serolis gracilis ; with this figure may be com- 

 pared PI. I. fig. 11, which represents the same appendage in Serolis cornuta; this 

 character is so trifling, that if it were not regularly present in all the deep-sea species, 

 and as regularly absent from all the shallow-water species, with which I am acquainted, 

 it would indeed be hardly worth mentioning. In a young specimen of Serolis antarctica 

 from the brood cavity of the mother, in which the appendages are still in a. comparatively 

 undeveloped condition without any hairs and spines, this prominence is conspicuous upon 

 the palp of the maxillipede, and is armed upon its upper surface with a short pointed 

 spine ; it is possibly the rudiment of some structure highly developed in the ancestors 

 of the group. 



NOTE. 



In the Plates which accompany this Report the figures of the animal.-^ tiiemselves 

 were in most cases drawn by Mr. Mintern from the actual specimens ; the appendages 

 were lithographed by him from my drawings. When not otherwise stated the figures are 

 maofnified from 10 to 30 diameters. 



(ZOOK. CHAU. EXP. — PART XXXIII. — 1884.) Kk 12 



