44 BOARD OF AGRICULTURE. 



The Peacock-lice (Philopterus faldcornis N., P. reclangula- 

 tus N.) are very common on the peacock. 



The Cat-louse (Tricliodectes subrostratus Nitzsch), Figure 

 39, is one of the parasites of the house cat. This species is 

 whitish, with the head and thorax pale honey-yellow. 



The Goat-louse ( Trichodectes caprce Packard, probably the 

 same as T. limbatus Gervais), Figure 40, lives with other 

 species upon the domestic goat. It is reddish yellow, trans- 

 versely Barred with reddish brown, the abdomen edged with 

 red. 



SUB-CLASS, ARACHNIDA. 



ACARINA (Mites). 



These are characterized by their simple,' usually rounded or 

 oval bodies, in which there is no distinct separation into 

 thorax and abdomen. They have eight legs, which are gen- 

 erally short, but when young many of them are six-legged. 

 The species are numerous. Their habits are very 

 diverse ; many are parasitic upon man, various quadrupeds, 

 birds, reptiles, insects, etc., some externally and others in- 

 ternally. Species have even been found within the abdo- 

 minal cavity and skull. Other species live under the water, 

 and are parasitic on mollusca. Many attack plants and prove 

 very injurious. Others are carnivorous and prey on small 

 insects. Some, like the meal-mite, sugar-mite, cheese-mite, 

 fig-mite, and many others attack and greatly injure articles of 

 food. Many lead a solitary, wandering life, others occur 

 together in vast numbers at certain times. 



DERMANYSSUS DugGS. 



The insects of this genus are small, soft-bodied parasites, 

 which infest various birds, bats, insects, and some of them 

 are at times parasitic upon man. 



The fifth joint of the palpi is smallest. The lip is sharp. 

 The mandibles of the male are forceps-like, with long hooks ; 

 those of the female ensiform. The anterior feet are the 

 longest. Young with six legs. 



Dermanyssus gallinoe is found among the feathers of the 

 domestic fowl, and lives by sucking the blood. 



