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in certain points from the animal as described by Philippi; and 

 Dr. AUman thought it not impossible that these differences 

 would indicate a distinct species, which might be noted under 

 the name of C. destructor, as distinguished from the C. tere- 

 brans of Philippi. As, however, it is by no means improbable 

 that the differences in question are referable to slight inaccu- 

 racies in the memoir of the continental zoologist, the proposed 

 distinction was considered purely provisional, to be confirmed 

 or rejected according as actual comparison of specimens shall 

 decide. The following summary of the generic characters of 

 Chelurus, more condensed than that given in the memoir of 

 Philippi, was proposed by Dr. Allman : 



Chelurus, Philippi. 



Gen. Cha. — Body not compressed; head distinct; superior 

 antenncB shorter and more slender than the inferior, and con- 

 sisting of a peduncular portion, which supports two unequally 

 developed rami.* Inferior antenna large, not divisible into a 

 distinct peduncle and ramus. Mandibles strong, palpigerous ; 

 furnished with a molar tubercle, with transverse ridges. First 

 pair of maxillae strong, pyramidal, palpigerous ; second pair 

 lamelliform. Maxillary feet large, bearing a palp-like stem, 

 and united at their origin, so as to constitute a great opercular 

 lip, covering all the other organs of the mouth. Thorax com- 

 posed of seven distinct segments, with the epimerse distinct, 

 and moderately developed. First two pairs of thoracic legs, 

 didactyle ; five remaining pairs terminated by a small, unop- 



* Philippi takes no notice of this character of the superior antennae, and 

 simply describes them as setaceous, with seven articulations ; whereas the 

 number of articulations, in the animal I have examined, are three in the pe- 

 duncular portion, and six in the larger ramus. I cannot, however, help be- 

 lieving that this excellent naturalist has, in the hurry of examination, over- 

 looked the real form of these antennae ; otherwise I would feel well inclined to 

 consider the character in question as affording sufficient grounds to separate 

 generically the Irish from the Mediterranean amphipod. 



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