COLLECTED AT PLYMOUTH IN 1888-89. 145 



collected by us during the past year has been very great, but I am 

 satisfied that I have not allowed a species to escape my notice, and 

 the above-mentioned forms must have been absent, during the past 

 year at all events, from the open sea in this neighbourhood. 



Having had access to only a limited number of systematic works 

 on the Copepoda I am obliged to confine myself in the descriptive 

 part of this paper to references to the following works. Brady's 

 Monograph of the British Copepoda, three vols. Brady, Eeport 

 on the Copepoda collected by H.M.S. Challenger, 1883. Claus, 

 Die freilebenden Copepoden, 1863. Ibid, Neue Beitrage zur Kent- 

 niss der Copepoden, Arbeit aus dem. zool. Inst. Wien, 1880-81. 

 Giesbrecht, Die freilebenden Copepoden der Kiele Foehrde^ Vierter 

 Bericht der Commission zur wiss. Untersuchung der deutschen Meere 

 in Kiel, 1882. Canu, Les Copepodes libres Marins du Boulonnais, 

 1888. Thompson, Proceedings of the Liverpool Biological Society, 

 vols, i and ii, 1887 and 1888. 



Family— CALANID^. 

 1. Cetochilus septentrionalis, Goodsir. 



CETOCHiLrs HELGOLANDicus, Claus. Die freilebenden Copepoden, p. 171, Taf. xxvi. 

 Caianus finmaechicus, Brady. Monogr., i, p. 38. 



— — Giesbrecht. Copepod. Kieler Foehrde, p. 156. 



— — I. C. Thompson. Proc. Liv. Biol. See, ii, p. 63. 



This genus was found at all seasons of the year in the surface net, 

 though seldom in considerable numbers, apparently it is more abun- 

 dant towards the end of the autumn, but in the majority of gather- 

 ings it is altogether absent. 



In adopting the generic name Cetochilus in preference to that of 

 Caianus I am following the example of Claus, whose arguments in 

 favour of retaining Eoussel de Yauzeme's name for the genus 

 appear to me to have more weight than the argument based on the 

 uncertain identity of Miiller's Cyclops longicornis with Gunner's 

 Monocidvs fnmarchicus. For the discussion of the subject, vide 

 Claus Neue Beitrage zur Kent, der Copep., Arb. Zool. Inst. Wien, iii, 

 3, and Brady, Challenger Eeports, loc. cit. 



2. Paeacalanus paevus, Claus. PI. XI, figs. 1 — 3. 



Calantjs paevus, Claus. Freilebenden Copepoden, p. 173, Taf. xxvi and xxvii. 

 Paeacalanus paevus, Claus. Neue Beitr. zur Kent, der Copep., Arb. Zool. Inst. 



Wien, iii, 3. 

 — — Canu. Copep. libres Marlus du Boulonnais, Bull. Scient. 



de la France et de la Belg., iii ser., 1 ann., p. 81. 

 NEW SERIES. VOL. I, NO. II. 10 



