100 Illinois State Laboratorij of Natural History, 



Pupae constantly found in sand galleries with this larva 

 have a pair of strong frontal hooks and are provided with 

 cottony respiratory tufts on the thorax. Length about .32 

 inch. 



These larva? and pupae were taken in numbers under rocks, 

 a short distance within the mouth of Cedar Creek. Young 

 short-nosed gars {L. phttystomus) had invaded the creek from 

 the bay and were busily probing the crannies and feeding on 

 the insects. One hundred and eighty-three larvae and forty-two 

 pupas were counted in the stomach of a single gar about nine 

 inches long. 



Chironomus, larva (2). 



About equal to (1) in size. Head pale brown, under side 

 black. Two eye-specks. Labium with four teeth on each side; 

 median tooth shorter than the two next it. Hairs of anterior 

 pediform appendage rusty. A single pair of small club-shaped 

 (respiratory?) appendages at posterior edge of the penultimate 

 segment. Anal papilla; conspicuously enlarged distally. Less 

 common than (1), but more widely distributed. 



Localities: Willow Slough, Cedar Creek, Broad Lake, 

 Wood Slough. 



Chironomiis, larva (3). 



Small; the largest of two examples taken, only .24 inch 

 long. A single eye-speck. Posterior segments without fleshy- 

 respiratory appendages. Anal papillae apparently jointed. 



One example each from Willow Slough and Cedar Creek. 



Chironomus, larva (4). 



A single very large larva, 1.38 inches long, from Ballard 

 Slough, seems to differ from all the preceding. Head black 

 beneath ; eye-specks two. Labium with a large truncate median 

 tooth, with a small tooth each side of it ; outside the latter, 

 two other large truncate teeth, — about four teeth, large and 

 small, on each side. Posterior segments without fleshy respi- 

 ratory appendages. Anal papillae not jointed. 



Chironomus, larva (5). 



A very small pupa (.12 inch long) taken August 7 within 

 the mouth of Cedar Creek still retained its larva skin, the 



