490 Messrs. T. and A. Scolt on 



more in)portant points of difference between this parasitic 

 Copepod and Canuella, and also the close relationship between 

 these two and the genus Longipedia, Claus. 



Sunaristes paguri, Hesse. 

 (PI. XT. figs. .1-10; PI. XIT. figs. 2-7.) 



1867. Sunmistes payuri, Hesse, Ann.des Sci. Nat. s6r. 5 (Zool.), vol. vii. 



p. 206, pi. 

 1884. Longipedina pac/uri, W. Miiller, Archiv f iir Naturg. Jalirgang50, 



Band 1, p. 19, pi. xiii. 



Description of the Female. — Figure 1 (PI. XI.) represents 

 an adult female of Sunaristes paguri from the Cromarty 

 Firth: it is an elongate and comparatively slender Copepod, 

 and measures fully 3 millim. (|- of an inch) in length, exclusive 

 of tail-set£e ; the first body-segment is somewhat more robust 

 than the others, the rostrum is large and conspicuous ; the 

 first abdominal segment, which is about equal in length to 

 the second and third together, is composed of two completely 

 coalesced somites, and is provided with hook-like appendages 

 on the underside and near the proximal end (fig. 4, PI. XII., 

 exhibits these appendages seen ventrally) ; the caudal stylets 

 are fully twice the length of the last abdominal segment. 



The antennules (PI. XI. fig. 2) are short, moderately stout 

 and setose, and consist of five more or less subequal joints, 

 but the penultimate joint is rather shorter than the others. 

 The antennge (PI. XL fig. 3) are similar to those of Canuella 

 and Longipedia. The mandibles (PI. XI. fig. 4) and other 

 mouth-organs (PI. XI. figs. 5-7) also closely resemble those 

 of the same two genera. The swimming-feet resemble those 

 of Canuella^ except that the inner branches of the fourth pair 

 are proportionally somewhat shorter (see PI. XII. figs. 2 and 3, 

 which represent the first and fourth pairs). The fifth pair 

 (PI. XL fig. 8), which are somewhat rudimentary, are each 

 lurnished with a long and moderately stout seta on the outer 

 angle and with tiiree elongate spines interiorly. 



Description of the Male. — The antennules of the male 

 SunaristiS (PI. XL fig. 10), which, like those of the female, 

 are short and stout, terminate each in a strongly developed 

 hand with a stout brownish-coloured movable claw ; they 

 form powerful grasping organs and by their robust structure 

 give the Copepod a somewhat remarkable appearance. The 

 antennae, mouth-organs, and swimming-feet are all more or 

 less similar to those of the female, with this important excep- 

 tion, that the first two joints of the inner branches of the 

 second pair of feet are produced distally into strong and some- 

 what spiniform processes that extend almost to the extremity 



