REPORT ON THE SCHIZOPODA. 171 



Willemoes-Sulim under the name of Euphausia simplex, but unfortunately wanting in 

 the collection. 



What distinguishes these larvae at the first glance is the very peculiar armature 

 of the free edges of the carapace, which are coarsely and elegantly denticulate in a 

 regular pectiniform manner, the denticulation being quite continuous all round in 

 the Calyptopis stage described by Dohrn, whereas in the Furcilia stage represented 

 here it is interrupted by the lateral emargiaations of the frontal margin, from which 

 the eyes project. 



The solitary specimen in the collection (fig. 30) has a length of nearly 5 mm., and 

 evidently corresponds, as regards the development of the limbs, to the first FurcHia 

 stage of Euphausia pellucida (PI. XXIX. figs. 4, 5), from which, however, it difi"ers, not 

 only in its much larger size and the above-mentioned peculiar armature of the carapace, 

 but in some other points to be set forth in the sequel. 



The carapace is comparatively very large and tumid, and has the inferior margins 

 strongly arched in the posterior part and somewhat incurved anteriorly to the middle, as 

 also terminating anteriorly in an acutely produced angle. Posteriorly, it juts forth in the 

 middle as a rather strong, spine-like projection, and is, moreover, provided in the middle 

 of the dorsal face with a distinctly marked rounded crest. The frontal plate is very large 

 and broadly rounded at the extremity, and coarsely denticulate along the terminal edge, 

 the denticles being somewhat larger than those occurring along the inferior margins of 

 the carapace. 



The tail is comparatively slender, and has the edges of the rounded epimera finely 

 serrate. The third segment juts out posteriorly as a small but well-defined dorsal 

 projection. The last segment is but little longer than the preceding, and quite smooth. 



The eyes are rather large and projecting, of a slender clavate form, with the comese 

 comparatively small. 



Of limbs, the antennulse, antennae, mandibles, two pairs of maxillae, and the 

 maxillipeds are distinctly developed, exhibiting, it would seem, a structure closely 

 resembling that in the corresponding stage of Euphausia pellucida. In addition, as in 

 that stage, the first trace of the anterior pair of legs and of the first pair of pleopoda has 

 appeared, both having as yet merely the form of smaU bud-like processes. 



The telson (fig. 31) is very large, almost equalling in length the three preceding 

 segments taken together, and gradually expanding towards the apex, which is broadly 

 truncate and slightly emargiuate in the middle. The number of spines is as usual 

 fifteen ; meanwhile both the lateral and three outer on each side of the terminal ones are 

 remarkably large and spinulose at the edges, whereas the seven median arc very small, 

 especially the middle one, which is, moreover, cpiite smooth. The lateral spines are 

 placed at the last third of the length of the telson ; and of the three outer spines of the 

 terminal edge, the middle one is much the largest, projecting far beyond the rest. 



