• REPORT ON THE CUM ACE A. 21 



carapace. Pseudorostral projection somewhat produced, obtuse at the tip, and limited 

 below on each side by a distinct angular notch. Ocular lobe extending along the dorsal 

 side of the pseudorostral projection to its tip, only slightly dilated at the apex and pro- 

 vided with but few corneal facets. Segments of trunk angular, with three longitudinal 

 dorsal crests. Integuments highly indurated. Colour uniformly whitish. Length about 

 5 mm. 



Remarks. — The present species is at once distinguished by the remarkable sculpture 

 of the carapace and the very strongly indurated integuments. Although the sole specimen 

 is incomplete, it may without any doubt be referred to the genus Cyclasjiis. 



Description. — The specimen examined wants the whole posterior part of the body, as 

 also the terminal part of the first pair of legs. The preserved anterior division of the 

 body has a length of 2 mm., and the whole body may thus have been about 4^ or 5 mm. 

 long. 



The carapace (see figs. 24, 25) is highly remarkable for its strongly marked sculpture. 

 It is rather gibbous in its hinder part and exhibits two very strong transverse crests 

 running across the dorsal surface and continued down the sides towards the infero- 

 posterior corner, where they unite almost at a right angle (see fig. 24). Of these crests 

 the anterior is placed immediately behind the frontal lobe and is uninterrupted in the 

 middle, whereas the posterior is divided in the middle line by a distinct notch at about 

 the posterior third of the length of the carapace (see fig. 25). Both crests are connected by 

 a median longitudinal keel and two lateral ridges, whereby the middle part of the carapace 

 is divided into four depressed areas, two dorsal and two lateral, the latter rather large and 

 of an irregularly oval or rounded triangular form. From the anterior crest, moreover, two 

 slight ridges run forward on each side, the one towards the base of the pseudorostral 

 projection, the other disappearing at some distance from the antero-lateral angle of the 

 carapace. Behind the posterior crest, finally, there occur on the dorsal surface three longi- 

 tudinal keels, each terminating in a somewhat rounded laminar projection at the posterior 

 edge. The pseudorostral projection is rather produced, obtusely triangular in form, and 

 limited below on each side by a distinct angular notch. The ocular lobe (fig. 26) is very 

 narrow and continued along the dorsal side of the pseudorostral projection to its very 

 apex ; it is but slightly dilated at the tip and exhibits a few rather small corneal facets ; 

 of pigment, on the other hand, no trace could be detected in the specimen examined. 



The four exposed segments of the trunk are at a much lower level than the carapace 

 and exhibit a somewhat angular form, the dorsal surface being scalloped out on each side 

 of the middle line, or provided with three longitudinal crests. As usual, the three 

 posterior segments are rather smaller than the anterior and connected by very movable 

 articulations. 



All the integuments are very strong and highly indurated, exhibiting under the 

 microscope a closely granulated structure. 



