GAMASIBS. 



179 



CASE upon them. Of those that have a single shield on the back and 

 none on the belly, he makes the genus Monostaspis. Those that 

 have one shield on the back and one on the belly, he makes 

 Diplostaspis. Of those that have one on the back and two on 

 the belly, he makes Tri-staspis. Those with a divided shield on 

 the back and one below, he calls Heterostaspis. One that has 

 remarkably thick anterior legs, with the claws developed into 

 something like an anchor without a caruncle, he calls Leiostaspis, 

 and so on. These have all very much the same facies, and require 

 careful examination to distinguish them from each other. For 

 our purpose it will be sufficient to notice the commonest and the 

 most remarkable. 



The commonest is perhaps : — 



Diplostaspis vespertilionis (Acarus vespertilionis, Herm. Apter. p. 84, 

 pi. I, fig. 14, 1804; Pteroptus vespertilionis, Duf. Ann. Sc, Nat. 

 1832 ; Sarcoptes vespertilionis, Koch, in Herrich-ScafF. Ins. Deutsch. 

 Heft 167, tab. 23 ; Dermanyssus albatus, Koch, Deutsch. Crust. Myr. 

 and Arach. h. 24, 168, 5 (young state) ; Dermanyssus arcuatus, Koch. 

 id op. h. 24, 168, 2 ; Diplostaspis arcuata, Kolenati, Sitz. Akad. Wiss. 

 "Wien. 1858, i66).— 25. Enlarged figure of ditto ; 26. Specimens of 

 ditto (i slide). 



Diplostaspis vespertilionis. 

 Copied from Hermann's early figure. 

 Half a line in length. 



Ditto (D. arcuata Kol.) 

 Copied from Kolenati's better and later tigure. 

 o"oois of a Parisian metre in length. 



Yellowish cream coloured, with dark or purplish markings ; very 

 frequent on Panugo noctula throughout Europe. We have noted 

 what appear to be synonymes given to it by various authors. 



