HARRIS : CRAYFISHES GENUS CAMBARUS. 87 



escaping pursuit, we infer from the fact that we repeatedly- 

 caught the animals in the chambers above, where they re- 

 main quietly instead of attempting to disappear into the apart- 

 ments below." 



He generally found a single male or female in a burrow, the 

 latter, in March or April, carrying eggs. Sometimes, when 

 very numerous, the windings of the upper part of the burrows 

 would accidentally meet ; each individual, however, seemed to 

 remain in its own apartment. 



A male and a female were found in one of the burrows. He 

 was inclined to believe that the male goes in search of the female, 

 since one was found "walking over the surface of the ground." 



"In the spring, and, we are told, in the fall also, the bur- 

 rowing crawfish builds over the holes of its burrow a chimney 

 of the maximum height of one foot, but most generally lower. 

 This chimney is circularly pyramidal in shape, is constructed 

 of lumps of mud varying in size, irregularly rolled up one 

 upon another, and intimately cemented together. Its exte- 

 rior has a rough and irregular appearance, whilst the interior 

 is smooth and as uniform as the subterraneous channel, having 

 the same diameter as the latter. The cementing of the suc- 

 cessive balls of mud is easily accounted for when we bear in 

 mind that the latter are brought up in a very soft state, and 

 that their drainage and subsequent solidification, on their ex- 

 posure to the atmospheric air and rays of the sun, is all that 

 is required to unite these parts." 



As to the actual method of working he made no observations, 

 except that the work was performed at night, and that the find- 

 ing of the imprint of the second and third pairs of claws indi- 

 cated that after the parcels of mud had been brought to the 

 surface — probably "embraced between the chest and large 

 claws, as suggested by Godman" ('60) — they were arranged 

 and fixed in definite place by means of these organs, 



"The closing of the aperture," he concluded, "is accom- 

 plished by bringing up several pellets of mud, depositing them 

 temporarily on the edge of the chimney, and then drawing 

 them back into close contiguity." 



"The number of chimneys, distributed without regularity, in 

 one particular locality, is often very great. We have seen 

 localities where the holes could be traced from the edge of the 



