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semblance to the great claws of a lobster, with which 

 they devour solid particles of cheese. These structures 

 in the bee parasite are slender, hollow, needle-like parts 

 which serve both to pierce the trachea of the bee and 

 to imbibe its blood. The cheese mites have no special 

 respiratory organs, and in this respect they resemble 

 the male Tarsonevius, whilst, as we know, the female 

 Tarsonetnus possesses a tracheate breathing system. 



Without wearying the reader with technical detail 

 which only skilled observers can appreciate, it may be 

 useful all the same to direct the attention of the amateur 

 microscopist, who may be examining Tarsonemus for 

 his own pleasure, to the various limbs. He will find 

 that the first pair of legs is terminated in a single 

 claw beneath which is a delicate pad or ambulacrum. 

 The second and third limbs each possess two claws with 

 ambulacrum. The claws are divergent. The last pair 

 of legs in the female terminates in a pair of long sweep- 

 ing hairs. The male, readily distinguished by its 

 smaller size, will be found to have a short delicate 

 spine and only one long hair at the termination of the 

 last limb. In the adult cheese mites all the legs are 

 terminated each in a single claw. With only one ex- 

 ception, all the colourless mites hitherto found in 

 association with bee hives are of the same sub-order and 

 general aspect as the cheese mites, and it is hoped that 

 with this brief enumeration of distinguishing marks no 

 difficulty will be experienced in recognising these less 

 important and more or less casual associates of the bee. 



The Respiratory System of the Bee. 



The part of the body of the bee which is inhabited by 

 the parasite of acarine disease is a very restricted region 

 of the respiratory system. The breathing of a bee is 

 effected by means of a series of tree-like branching tubes 

 termed tracheae. These tubes arise originally as paired 

 indimplings of the surface along the sides of the body. 

 In the bee there are ten pairs of these. As development 

 proceeds, the hollow inturned tubes extend further and 

 further within the body, branching in all directions 

 until eventually they form an extensive network in 

 contact with the whole of the tissues. The inner 



