296 Prof. J. C. Schiodte on the 



that the mandibles in the whole of their extent are of unusual 

 height, almost as high at their apex as at their base, and 

 consequently, in this respect, very different from what is seen 

 in the two preceding types. We observe besides that the 

 mandibular springs of the lower lip are so short that they by 

 no means, as in Eleutherognatha and Trochalognatha, 

 almost reach as far back as the inner corners of the bases of 

 the mandibles ; finally, it is seen that the second pair of 

 maxillge are to that extent involved by the maxillipeds that 

 only a small strip of their middle portion becomes visible 

 without preparation. The proportion in which the different 

 oral limbs take part in the composition of the cone described 

 appears still more clearly if this is examined from below, 

 facing the apex of the cone : the lower margin of the man- 

 dibles is seen uncovered, whilst the second pair of maxilla? 

 are entirely hidden except the middle portion, the narrow 

 maxillipeds covering the central part of the cone with their 

 coalesced minor lobes. If we bend the maxillipeds back, it is 

 easily perceived that their use is to cover the maxillae and fill 

 out the space left between them ; the upper face of the stipes 

 is carinate and fits in between the second pair of maxillae ; the 

 inner lobes are coalesced and close the space between the 

 grinding-teeth of the mandibles ; the outer lobes fill out the 

 space all the way forwards to the upper lip, covering the 

 inner parts of the first pair of maxillae. The maxillipeds 

 have no palpi. The second pair of maxillge are distended, 

 cushion-like ; and only the apices of their lobes carry spines 

 and set£e. The first pair of maxillae have large cardines, 

 large stipites with dilated apices, but no inner lobes ; the 

 outer lobe of each maxilla carries on its apex five powerful 

 spines arranged in two rows, and a considerable number of 

 stiff setae. The palpus consists of but one joint, broad, oval, 

 arched, with truncate apex, which is furnished with smooth 

 and ciliated spines ; whilst the inner margin is slightly curved 

 and serrate, with a small spine in each indentation of the saw, 

 and a short thick thorn in the inner corner. If now, finally, 

 all the appendages of the mouth are taken away except the 

 mandibles (as we have done in examining the previous ex- 

 amples), the hypostoma appears, with the articular sockets of 

 the two pairs of maxillae, and also the whole of the lower lip. 

 The short and broad form of the latter reminds us of Capi-ella, 

 whilst the inner lobes are still more reduced than in Aiionyx ; 

 but the mandibular springs are much thicker than in either 

 of these two types, and of a peculiar curved shape. At 

 the same time the anterior lobes, though in shape and thick- 

 ness rather recalling the same parts in Ca^rellaj differ from 



