i;|4 Mr. H. Gmney on the Copepod 



XIV. — .1 Drftrr'i/ifinn nf the Capppnd Cylin(lro|i<!ylliis brcvi- 

 cornis, Van Domre. and of a new species o/ D'Aicythoiiip- 

 souia, Scott. Hy Rohkrt Gurney, M.A. 



[Plat€3 V.-A'II.] 



CrLTSDROF^Tr.Lvs nTfFvrroRyrs was first rlrsoril)e(l l)y Van 

 Douwe from two male spocimcns taken in l)raokish water at 

 Greifswakl, and a sin}i;le female was found by Brehm in 11)14 

 in a collection made in fresh water at Sebenico in Dalmatia. 

 In neither case did the material permit of the ])nblioati(>n 

 of a full description, and as I have had the opportunity of 

 examining a number of specimens, and liave come to tlie 

 conclusion that a new genus should ])e formed for its 

 reception, I think it advisable to give a further account of 

 it with figures. 



HoRsiELLA, gen. nov. 



Body vermiform, tlie abdomen not distinct from the tliorav. 

 (ienital segment partly or wliolly divided into two. First 

 pair of antennrc short, with few joints. Secoiul pair three- 

 jointed, without external ram\is. Mandible without external 

 ramus. Maxillipedes al)sent. Sv^imming-lcgs alike in both 

 sexes, the internal rami of two and the external of three 

 joints. Fifth pair of legs nnnnte, one-jointed. 



A comj)arison of the single representative of this genus 

 with Ci/lindropsyllus ahown veiy striking differences in struc- 

 ture, particularly with regard to the swimming-legs, Horsiella 

 approaching in this respect more nearly to the genera 

 Leptocaris and jyArri/t/mw/isunia. It ditters from these two 

 genera and also from Cyl'indropsiilhis in the absence of the 

 external ramus of the second ])air of antennje and of the 

 mandibles, and in the absence of the maxillipedes. 



Horsiella brevicornis (Van Douwe). (Pis. V. & VI.) 



Ci/lhiflropsi/llus breviconiiD, Vnn Douwe, Zool. Anz. xsviii. VDO't, 

 p. 437; Brehm, Zool. Anz. xliii. 1914, p. 337. 



Shape of body cylindrical and vermiform, as in CyJindro- 

 j/st/l/us; the first segn)ent of the thorax marked off from the 

 liead by a slight dorsal groove (xtei.diiiii: |)aitly down the 

 sides. Integument thin and without markings. The genital 

 segment is completely se|)arate(l into two in the male, but 

 in the female the line of division does TU)t exteiul across the 

 ventral surface, 'i'he fifth abdominal segment is twice as 



