10 G. O. Sars. 



Each half is strengthened by a longitudinal chitinous stripe, 

 and terminates in a freely-projecting incurved lobe, finely 

 ciliated at the tip. This part has generally been described 

 as the 1st pair of maxillæ; but this, I believe, is quite 

 erroneous. 



Each of the true 1st pair of maxillæ (fig. 6) has the form 

 of a curved, highly chitinised piece, the inner extremity of 

 which is strongly expanded, almost securiform in shape, with 

 the anterior corner somewhat produced and armed with a 

 transverse row of short, but rather coarse, dark horn-coloured 

 spines. The edge of the expansion likewise carries several 

 small spines, and is moreover densely clothed with stiff 

 bristles. 



The 2nd pair of maxillæ (fig. 7), erroneously described by 

 other authors as a pair of maxillipeds, are of a much more 

 delicate structure. They each project inside as a linguiform 

 masticatory lobe densely clothed with rather slender bristles, 

 and exhibit outside a short and obtuse, somewhat membranous 

 expansion, apparently a rudiment of a palp. 



The legs are very numerous, and it is indeed a matter of 

 great difficulty to determine their exact number, because they 

 posteriorly become gradually so very much reduced in size 

 and so densely crowded as hardly to admit of being counted. 

 In every case, their number may amount to more than 60 

 pairs in all. In the foremost part of the trunk, the mesosome, 

 each segment carries but a single pair of legs, but more 

 posteriorly, several pairs are found attached to the same seg- 

 ment. In structure they also differ rather inarkedly, though 

 there is a gradual succession in their modifications, the anterior 

 pairs being pronouncedly prehensile, whereas the posterior 

 pairs would seem successively to lose this character and to 

 become merely respiratory. The latter function may, how- 

 ever, also in part be attributed to the anterior pairs, and. 



I 



