76 [March, 



Irelaud. Chief hosts are the stoat (Mustela ermineaj, the weasel 

 (Mnstela ■yiivalis), and the liauk vole (Evotomys glarenlus). C. walkeri 

 has uot been recorded from the Gontiueut. 



25. Ceratophyllus mustelae Dale (1878). 

 (Figs. 53, 54). 



Occiput usually with a median row of four bristles. Mid- and 

 hindfemora with one lateral bristle. Stigma of eighth tergite broader 

 than the tail of the receptaculum seminis. 



(^ . First midtarsal segment with a long and slender apical bristle 

 reaching a little beyond apex of second segment. Wide portion of 

 eighth tergite without hairs on inside at dorsal edge, and with five or 

 six bristles on outside. Eighth sternite (fig. 53) resembling the runner 

 of a sleigh, and only slightly curved, proximally widened, with the dorsal 

 angle of the widened portion directed distad, not upwards. Along 

 ventral margin of eighth sternite numerous thin and short bristles, 

 and one long one on each side at apex. Apical lobes of eighth sternite 

 broad, bearing short fringes. Pi-ocess P of clasper long and rod-like. 

 Finger widest near centre, the anterior margin nearly straight, the 

 posterior margin convex ; at widest point one stout obtuse bristle, and 

 further upwards at about ^f-, and ^/o from this bristle to apex two thinner 

 pointed bristles, and a very thin one further upwards. Ninth sternite 

 narrow. Apical hooks of parameres long and slender. The manubrium 

 and internal dorsal portion of ninth tergite form an acute angle, the 

 point of which is rounded off. 



? . Seventh sternite (fig. 54) with shallow sinus, upper lobe 

 slightly more pointed but a little less projecting than lower lobe. Two 

 long bristles and a short one below stigma. Stylet short, only half 

 as long again as it is broad, both lateral bristles long. Head of 

 receptacuhun seminis much longer and broader than the tail. 



Common in England and Scotland, not recorded from Ireland. 

 Occurs on many hosts ; among which may be cited long-tailed field 

 mouse (Apndemus sylvaticusj, bank vole (Evotomys glareolus), and the 

 stoat [Mnstela erminea). 



26. Ceratophyllus melis Walh. (1856). 

 (Figs. 55, 66). 

 The largest Bi'itish species of this genus. 



Rostrum reaches to the tibia, being longer than in any other 

 British fiea. Stigmata large. Forefemur with a single bristle on 



