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Gen. 5. PterinOpSyllUS, Brady, 1880. 



Syn : Lopliophorus, Brady (not Temminch). 

 Cyclopella, Claus. 



Generic Characters. Body robust and somewhat depressed, with the 

 anterior division moderately dilated, the posterior less narrow than usual. Head 

 coalesced with the 1st pedigerous segment, and terminating in a blunt rostrum 

 projecting downwards. Caudal rami short, with the 2 middle apical setae very 

 strong and densely ciliated. Anterior antennae short and stout, with the number 

 of articulations reduced, and clothed with unusually strong pennate setae; those 

 of male of much larger size and strongly hinged. Posterior antennae likewise 

 short, and only 3-articulate, the last 2 joints being united. Mandibles with the 

 cutting part considerably expanded and coarsely dentate; palp comparatively 

 slender, with the outer ramus small and undivided, inner ramus biarticulate. 

 Maxillse with all the constituting parts well developed. Anterior maxillipeds very 

 stout, with 3 well-defined terminal joints armed with strong spines. Posterior 

 maxillipeds with the terminal part very fully developed and composed of 5 joints, 

 the 1st much larger than the others. Natatory legs strongly built, with short 

 and blunt spines outside the outer ramus; inner ramus of 1st pair in male pre- 

 hensile, that of 4th pair more or less reduced in female, normal in male. Last 

 pair of legs comparatively small and not extended laterally, being composed of 

 3 more or less lamellar joints, somewhat different in the two sexes. 



Remarks. This genus was established in the year 1878 by Prof. Brady, 

 to comprise a peculiar Copepod found by him off the British coast. As, however, 

 the generic name he proposed, Lophophorus, had been preoccupied for a genus 

 of birds, he changed it in the year 1880 to Pterinopsyllas. The name Cyclopella 

 proposed by Claus is of later date, and must yield to that given to the genus 

 by Brady. 



The systematic position of the present genus has remained somewhat 

 doubtful. In some respects it recalls certain genera among the Harpacticoida, 

 and, indeed, it has been placed within that group in the list of Crustacea from 

 Northumberland and Durham published by Norman and Brady. I think, however, 

 that its place within the group Cyclopoida cannot at present be disputed. On 

 the other hand, owing to the peculiarities observed in this genus, it might be 

 thought necessary to establish for its reception a distinct family, Pterinopsyllidce. 

 Indeed, I was at first much inclined to do so; but after having become acquainted 

 with the preceding genus, Cyclopetta, which in some respects exhibits an evident 



