302 CHAS. D. SOAR ON A SPECIES OF 



contained males, females and nymphs. The colouring these mites 

 usually exhibit in life had been lost in the preservative solution, but 

 they showed all the external structure necessary for identification. 

 At first sight they are very like a mite recorded by Mr. Halbert 

 from Co. Waterford and since found in Northumberland, known 

 as SpercJion hrevirostris Koen. It is like it in colour, size, and 

 general appearance ; however, on closer inspection it is seen to 

 differ in at least three important characters : the skin texture, the 

 capitulum, and the genital area. The females vary very much in 

 size, but they are about the same as S. hrevirostris Koen., ovate 

 in shape. The skin, instead of being papillated as in S. hrevirostris 

 or S. glandulosus, is provided with a system of fine raised lines or 

 ridges ; these lines are not straight but more or less curved and 

 under a j-in. objective have very much the appearance of the skin 

 at the tip of the human finger (Fig. 4). On the dorsal surface 

 (Fig. 2) are two pairs of conspicuous chitinous plates, which Sig 

 Thor says have a bluish tint. The dermal glands are small. 



The distance between the small ends of the first pair of epimeral 

 plates behind the capitulum varies in different specimens, but I 

 found none that quite met (Fig. 1). 



The capitulum is short and broad ; it differs from S. hrevirostris 

 in the folds in the side walls. Walter points out that in S. lineatus 

 the folds number six or seven, whereas in S. hrevirostris there are 

 quite a number. 



The genital area (Fig. 6), which is about 0-30 mm. long and 

 0-20 mm. broad, differs from that of S. hrevirostris in having 

 the acetabula shorter, wider, and, as Sig Thor points out, when 

 viewed sideways are almost hemispherical and attached to a kind 

 of foot. 



The palpi (Fig. 5) do not show sufficient difference to call for 

 any remark, except that on the extensor edge of the third 

 segment there is one single bristle ; in S. hrevirostris there are 

 usually two or three. 



The anal glands vary a little in position in different specimens, 

 in some being in direct line with the anus, in others a little nearer 

 the posterior margin. 



The male (Fig. 3) requires no special note ; it is a little 

 smaller than the female. 



The nymph is about 0-80 mm. long ; provisional genital area 

 (Fig. 7) with four acetabula only. 



