212 ENTOMOLOGICAL SOCIETY 



Mr. Fairchild, in answer to a question, stated that the Fiji eye- 

 disease in its milder form lasts, in its acute stage, 4 or 5 days and 

 then gradually dies away. 



Mr. Banks read the following paper : 



A NEW SPECIES OF THE GENUS HALARACHNE. 

 By NATHAN BANKS. 



In 1847 P r f- Allman described a remarkable mite which he 

 had discovered in the nares of a seal from the Irish Sea. Unable 

 to place it in any of the then existing genera, he established for it 

 the new genus Halarachne, and named the species H. halichceri, 

 after the genus of seal on which it occurred. He characterized 

 the genus as follows : " Palps free, filiform, mandibles didactyle, 

 sternal lip bifid. Legs with last joints terminated by two hooks 

 and an intermediate three-lobed caruncle. Body entire, elongate, 

 subcylindrical, furnished anteriorly with a dorsal plate ; eyes 

 none." 



He placed the genus in the vicinity of Dermanyssus ; a posi 

 tion which I believe to be correct. For many years little or no 

 attention was given the mite. However, in 1884, Nehring, a 

 German mammalologist, obtained specimens from the same seal, 

 and published a note upon it. He maintained that it was related 

 to the Ixpdidae rather than to the Gamasida3, chiefly on account 

 of its shape, general appearance, and especially the posterior 

 position ef the stigmata. 



Kramer, the acarologist, saw the specimens and wrote a short 

 article upon the mite, dealing principally with its anatomy. 

 Haller in 1886 gave a few notes upon it. In 1889 Nehring pub 

 lished another note upon it. Its peculiar habitat is, doubtless, the 

 reason why so few specimens have come into the hands of acar- 

 ologists ; and thus the genus has rarely been mentioned or treated 

 in systematic works. 



A short time ago Dr. Motter brought me some examples of a 

 mite given him by Dr. Hassall, who took them from the bron 

 chial tubes of a seal that had died in the Zoological Park. At 

 first I thought it related to one of Kolenati's genera of bat-mites, 

 viz., Lepronyssus ; but soon discovered that it was a species of 

 Halarachne, closely allied to H. halichceri. The genera erected 

 by Kolenati in the Dermanyssida? have not been generally ac 

 cepted, and there is much uncertainty regarding them. But the 

 great difference in habitat, and doubtless the position of the stig 

 mata, will separate Halarachne from all other Dermanyssidae. 

 The breathing pore is situate just above the fourth coxa, and a 

 line from it extends around and behind the coxa. In Derma 

 nyssus the stigmata are a little farther forward. The mouth-parts 



