VJ 



ENUS LITHOTRYA. 349 



L. dorsalis is covered with strong points, but in the 

 other species is, as usual, smooth. 



Outer Maxilla. — The inner margin is slightly concave, 

 and in L. truncata alone, the bristles are hardly continu- 

 ous, being interrupted in the middle part. The olfactory 

 orifices are only very slightly prominent. The spines on 

 all the tropin are more or less doubly serrated. 



Cirri. — The three posterior pair are elongated, with 

 their anterior surfaces not at all protuberant. The seg- 

 ments bear from three to five pair of spines, with a row 

 of three or four small intermediate spines ; there are, 

 as usual, some little lateral upper rim spines ; the dorsal 

 tufts contain some thick and thin spines mingled. First 

 cirrus is short, and placed not quite close to the second 

 pair; the basal segments are broad and thickly paved 

 with bristles. The second pair is rather short compared 

 with the third pair ; a varying number of the basal seg- 

 ments in both rami of both these cirri are protuberant, 

 and are thickly paved with bristles ; such segments are 

 more numerous and are broader on the anterior rami than 

 on the posterior rami. In L. cauta alone, none of the 

 basal segments in the posterior rami of the second and 

 third cirri are thickly paved with bristles. The pedicels 

 of the first three pair are irregularly covered with spines ; 

 those of the three posterior pair have the spines arranged 

 in a regular double line. Most of the spines are doubly 

 serrated. 



Caudal Appendages (PI. X, fig. 23 and 24), multiarti- 

 culate, with thin elongated segments fringed with short 

 spines; in length generally exceeding the pedicel of the 

 sixth cirrus, and in L. Nicobarica equalling half the entire 

 length of this cirrus. 



Stomach, destitute of caeca; oesophagus somewhat curled. 



Filamentary Appendages, none. 



Ovaria filling up the peduncle and surrounding the 

 sack, but not extending up to the bases of the scuta and 

 terga ; I saw the ova only in L. truncata; they were here 

 oval and large, being nearly ^ths of an inch in length. 



