550 NEW YORK STATE MUSEUM 



and mouth parts are relatively larger. The lateral filaments bear two 

 spinules at their apex, the posterior one minute. Each filament shows 

 a central tracheal branch, without distinguishable tracheoles and with a 

 rough prickly surface which is certainly not suggestive of a respiratory 

 organ. The circulation of the blood, easily seen in other parts of the 

 body, I could not observe in these at all. 



Respiratory tubes from the spiracles of the eighth abdominal segment, 

 wide apart, short, not half as long as the segment. The lateral filaments 

 of the tenth abdominal segment are short, bearing three setae, of which 

 the two exterior are longer than the filament itself: filament not surpas- 

 sing the tips of the claws. The two longitudinal tracheal trunks within 

 the body terminate in the tubes springing from the spiracles of the eighth 

 abdominal segment, but they are much stouter anteriorly where passing 

 the other spiracles, and they bend distinctly outward to meet the 

 spiracles of the prothorax. 



Antennae three-jointed, the second joint bearing at its distal end ex- 

 teriorly a pair of spinules close beside the base of the terminal joint. 



The brevity of the respiratory tubules on the eighth abdominal segment 

 is doubtless ancestral ; and the spinules on the lateral filaments may mean 

 that these filaments are but modified larval setigerous tubercles. The 

 function of the filaments is largely locomotor ; they are used as fins in 

 swimming. But they are also "outriggers," if we may so speak, serving 

 to maintain the proper position of the long abdomen while crawhng 

 about over submerged logs. 



Ch. serricornis was first taken June 20, and was quite common 

 for a month thereafter. The pupa was searched for, but not found. 



Corydalis 



Our sole species, C. cornuta Linn, is too well known to need 

 another description. It will be recognized by the characters stated in 

 the keys, and by Dr Lintner's figures, reproduced herewith as Plate 28. 



Family heme^robiidae 



This family has received little attention from entomologists in America. 

 I do not now recall a single American species whose life history is known 

 in full. A single species supposed to be aquatic has been twice reported 

 from the United States — once from New York state. It is gratifying 

 therefore to be able to add, another genus, Climacia, to the hst of 

 aquatic genera, and to make a slight contribution to the knowledge of 

 its habits and life history. 



