0. Harger Isopodafrom New England . 375 



segment embracing the bead, separated from it by sutures at 

 the sides, but united in the dorsal region. Fourth segment 

 longer than the other six segments together in the female, still 

 more elongated in the male, in which sex it is longer than the 

 three following segments with the pleon, while in the female it 

 is only four-fifths as long ; irregularly but not coarsely tuber- 

 culated, especially in the dorsal region. Last three segments 

 with their epimeral regions produced into salient angular tuber- 

 cles. Pleon elongate-ovate, tuberculated, a little longer than 

 the last three thoracic segments, with three transverse grooves 

 in the proximal region, the second continued at the sides, but 

 showing no distinct suture. Immediately behind this is a 

 prominent tooth on each side, directed outward and backward. 

 Tip of pleon not spiniform but only slightly attenuated and 

 obtuse. Opercular plates more than nine-tenths as long as the 

 inferior surface of the pleon. 



Length of female 10mm., male llmm.; diameter of fourth 

 thoracic segment, female l'2mm., male 0'52mm. Of the two 

 adult specimens obtained, fortunately a pair, the male, though 

 much the more slender, actually exceeds the female in length. 

 This relation of size in the sexes is unusual in the genus, the 

 females being generally considerably larger than the males, but 

 more specimens are necessary to prove the constancy of this 

 proportion. 



The specimens of this species were found adhering to Prim- 

 noa, from St. George's Bank. 



Astacilla Fleming, is synonymous with Leacia (Leachia) John- 

 ston, which is preoccupied. 



Eurycope robusta, sp. nov. 



Body oval, smooth and polished, breadth nearly equal to half 

 the length. Head longer than the first thoracic segment, pro- 

 duced medially into a short rostrum about half as long as the 

 basal antennular segments. Antennulae attaining the middle 

 of the fourth antennal segment; basal segment subquadrate, 

 bearing the second, much smaller, segment beyond the middle 

 of its superior surface; third segment slender; flagellum about 

 twice as long as the peduncle, multiarticulate. Antennae 

 thrice the length of the body at least in the female ; first three 

 segments short; fourth and fifth slender, subequal and together 

 as long as the body in the female ; flagellum long, slender and 

 multiarticulate. External lamella of maxillipeds subrhombic, 

 with the inner angle much rounded, the outer prominent but 

 not acute. First four thoracic segments short; fourth widest, 

 fifth and sixth suddenly twice as long ; seventh much the long- 

 est of all. First pair of legs shorter than the body ; carpus 

 exceeding the propodu's; second pair longer than the body; 

 third and fourth increasing slightly in length ; carpus and pro- 



