REPORT ON THE CUMACEA. 69 



greatest breadth, which about equals the height, occurring posterior to the middle. 

 The surface of the carapace is evenly vaulted, without any keels or excavations, but 

 exhibits a number of well-marked, rounded, nodiform protuberances, distributed rather 

 evenly, dorsally as well as laterally, the most anterior part alone being nearly smooth. 

 The ocular lobe is rather large and of oval form, but seems to want distinctly developed 

 visual elements. 



The exposed part of the trunk is not, as in the preceding species, arched over by 

 the posterior part of the carapace, all the segments being distinctly visible in their 

 whole circumference. They are rather shai'ply defined, with the posterior edge much 

 elevated. The last segment does not diifer either in size or in form from the anterior 

 caudal segments, and, like these, is without any trace of limbs. 



The tail is somewhat shorter than the anterior division of the body, with the 

 segments marked off from each other by deep constrictions. They are slightly keeled 

 laterally, and the penultimate segment exhibits, moreover, posterior to the middle, a 

 transverse sulcus, so that it is, as it were, subdivided into two segments. The last 

 segment (see fig. 21) is, as usual, somewhat dilated posteriorly and of pentagonal form, 

 the posterior edge being produced in the middle as an obtuse angle. 



The colour of the specimens, preserved in spirit, is whitish, with patches of brownish- 

 red, but may have been in the fresh specimens more uniformily reddish, as several 

 northern forms acc[uu'e a c[uite similar spotted appearance by the action of the spirit, 

 though originally more uniformly coloured. 



The antennulse (fig. 3), which ^jroject anteriorly from the subrostral notches (see 

 fig. 1), are of moderate length, with the first joint of the peduncle strongly curved and 

 somewhat shorter than the two others taken together. Of the latter the first is con- 

 siderably larger than the second. The outer flagellum (see fig. 4) is well developed 

 and composed of three joints, the last of which, however, is exceedingly minute and 

 might be easily overlooked. It is provided at the tip with the two usual ribbon-like 

 sensory appendages, besides a slender seta ; moreover, a small auditory bristle is found 

 affixed to the last joint. The inner flagellum is exceedingly minute, but on closer 

 examination it is found to be composed of two well-defined joints, the last of which is 

 provided at the tip with two diverging auditory bristles. 



The anteuuge (figs. 5, 6, «-) are quite rudimentary, constituting a simple, strongly 

 indurated, conical prominence, divided into two segments and without any trace of 

 bristles or spines. 



The anterior lip (figs. 5, 6) is comparatively large and of a rather peculiar shape, 

 forming a broad quadrangular plate projecting anteriorly between the antennse as a 

 rounded nodulose protuberance, and having the posterior edge sharp and broadly 

 incised in the middle. 



The posterior lip (fig. 7) is scarcely larger than the anterior, and of a very delicate 



