26 MONOGRAPHIA 



Field Campagnol, (Arvicola Agrestis). From which animal 

 I have also taken it myself, as well as from the Dormouse. 

 Mr. Thompson also sent another specimen taken from a 

 new species of Arvicola near Belfast. It appears however 

 to be by no means of frequent occurrence. 



2. H^EMATOPINUS SPINULOSUS. (Louse of the Rat.) 



Plate XXIV. Fig. 5. 



Pale fulvous yellow, spinulose ; occiput broad, nearly 

 obtuse; abdomen with the lateral margin of the first six 

 segments terminating with a tooth ; posterior pair of legs 

 very large and thick. 



Pediculus spinulosus. Burmeister Genera Insectorum, Order Rhynchota, 

 sp. 8. 



Pale fulvous yellow, thickly spinulose. Head large, sinu- 

 ated on the sides, somewhat quadrate, the anterior part 

 convex, with two depressed lines extending to the occiput 

 which is nearly obtuse, with a slight prolongation in the 

 centre. Eyes not visible ; antennae about the length of the 

 head, very thick ; the first joint largest, second, third and 

 fourth nearly equal, fifth smallest and conical; thorax 

 shorter than the head, transverse, lateral margin prominent, 

 basal angles acute; abdomen large, broad, obovate, segments 

 equal, the lateral margins of the first six ferruginous, termi- 

 nating in a strong tooth, beneath which rises a long bristle, 

 last segment terminated with two tufts of hairs ; legs thick, 

 the anterior pair short, posterior very large ; tarsi rather 

 small ; ungues thick and ferruginous. Length . 



Infests the common rat (Mus decuman us) from which I 

 obtained a few specimens. 



