12 G. O. Sårs. 



- — Animal. Head with the ocular protuberance very pro- 

 minent, occipital prominence but slightly produced, obtus- 

 angular, rostral part in male obtusely rounded at the tip, in 

 female triangularly tapered, apical spine in the former de- 

 flexed, in the latter procurved. Branchial legs with the 

 lower part of the exopodite divided at the outer edge into 

 several distinct setiferous lobules, appendicular lamella large, 

 securiform, epipodite in the middle pairs much produced ; 

 prehensile part of the 2 anterior pairs in male of the usual 

 structure. Caudal piece resembling that in L. siliqua, though 

 comparatively shorter and broader. Length of shell in adult 

 male 10 mm. 



Remarks." — This is a very beautiful species, somewhat 

 resembling L. siliqua in the shape of the shell, but com- 

 paratively shorter, and Avith the lines of growth much more 

 sharply marked, and arranged in a remarkably regular man- 

 ner. The enclosed animal differs also very conspicuously in 

 the far less produced occipital projection, and in the struc- 

 ture of the legs, the distal part of the exopodite having the 

 outer edge distinctly lobular. 



Description of the adult male. 



The shell measures about 10 mm. in length, and S^/s mm. 

 in height, and yet it is very probable, that under favour- 

 able circumstances it may grow to a still larger size, as 

 there is no apposed marginal area like that found in large 

 specimens of L. siliqua, as also in those of the succeeding 

 species. 



Seen from the side (fig. 1), the shell exhibits an oblong 

 quadrangular form, with the height somewhat exceeding half 

 the length. The dorsal margin is perfectly straight and hori- 

 zontal, though interrupted in the anterior part by the um- 



