686 



BIRD MITES. 



mentioned species, except that there is more red in it. Moreover, it can be distinguished 

 by the antennae, which have the second joint the longest and the third acute. The eves 

 too, are large and prominent. 



THE four creatures represented in the accompanying illustration are parasitic on birds 

 Ihe species shown in the upper left-hand corner is unpleasantly familiar to poultry- 

 keepers swarming among the feathers to such a degree that the hands are often covered 

 with these parasites when the fowls are plucked or even lifted up. They cling very 

 tightly, and are not easily brushed away, as their bodies are smoothly polished, and offer 

 scarcely any resistance. The colour of this species is pale straw. 



The upper right-hand figure represents 

 a parasite found on the common swan and 

 other aquatic birds, such as the bean goose 

 and Bewick's swan. It is coloured after a 

 rather peculiar fashion. The head, thorax, 

 and legs are bright chestnut, smooth and 

 shining ; the abdomen is white, except the 

 first segment, which is of the same colour as 

 the thorax. There is also a chestnut spot 

 on the third segment, and a row of short 

 liver-coloured bands runs down each side. 

 At the lower left-hand corner is seen a 

 parasite which is not very plentiful, but 

 which is found on various birds, such as 

 the rook, the raven, and blackbird. It has 

 a hard shelly surface, and is marked with 

 numerous dark bars. The last figure re- 

 presents the SICKLE-HORNED TICK, so called 

 from the shape of its antennte, which are 

 rather large, flattish, and curved. It is a 

 pretty species, its squared head being of 



a light chestnut colour, and highly polished. The abdomen is broad, rather flat, and of 

 a light tawny yellow, barred with deep red, and having the last segment of the same 

 colour as the head. It is parasitical upon the common peacock, and may almost invariably 

 be found after the death of the bird congregated in tolerable numbers about the base of 

 the beak 



IN tlje accompanying illustration are seen some details of the characteristic portions of 

 many Arachnida, most of which have been casually mentioned in the preceding pages. 



The two upper rows exhibit the manner in which various types of eyes are arranged, 

 and are valuable as showing how important are the eyes in distinguishing one genus of 

 spiders from another. The bold staring eyes on the right-hand side of the upper row are 

 those of the genus Nops, and, as far as is known, are unique among spiders. They are 

 large, black, glittering, and bear no slight resemblance to the glasses of "bull's-eye" lanterns. 

 The central figure represents the eyes of the genus Salticus, or Hunting Spider, and on the 

 extreme left are the eyes of Lycosa, or Wolf-spiders, which are set in a manner almost 

 precisely the reverse of the preceding. 



Passing to the right-hand figure of the second row, we come to the cephalothorax and 

 eyes of the new British spider, Dysdera erythina. The central figure gives a profile view 

 of the cephalothorax of a male Walclcenaera acuminata, showing the long, slender, vertical 

 process of its termination, and the manner in which the eyes are disposed upon it. On 

 the left hand of the same row is shown the elevated front of the cephalothorax belonging 

 to the genus Hersilia, showing the remarkable manner in which the eyes are arranged. 



The third row contains some specimens of grasping organs. On the right hand ia 

 shown the under surface of the base of mandibles, belonging, I believe, to the genus 

 Linyphia. The severe illness of 'the artist prevents me from ascertaining whether that 



Mtnopon pdllidum. 

 Nirmus drgulus. 



Docdphoru* cygn** 

 Goniddes falcicornis. 



