Localities in which Pellagra is Prevalent. 51 



thus obtain free transportation. It was collected in the 

 broken up shelters made of pebbles and found under rocks. 

 It is probably the owner of these shelters and a member of 

 the genus Hydropsyche. 



Body pubescent. Head small, and with three thoracic 

 somites, brownish black dorsally. Eye in a pallid area. 

 Jointed legs yellow, pubescent. Second and third thoracic 

 and six abdominal somites with whitish ventral branched 

 appendages. 



Possibly several species are represented among material 

 collected with the above. One example noted has a green 

 abdomen. Others show several protrusible finger-like ap- 

 pendages dorsal to the posterior false legs. The head has a 

 peculiar unfinished appearance, and is shorter and smaller 

 every way than the heads of other free-living larvae col- 

 lected. The pubescent body and long brush of hairs on the 

 false legs were generally loaded with sediment in the 

 streams of Bell County. Examples of what appears to be 

 the same insect from Benson Creek in Franklin County bore 

 very little such material. This same insect was collected at 

 Elk Lick Falls, July 14, 1893. 



Case-fly Larva No. 5. — A single example of this species 

 was taken from the Left Fork of Straight Creek, October 

 21, 1911. It resembles No. 4 in a general way, having a 

 fine pubescence over head and body, and being provided 

 with similar branched ventral appendages on the thorax 

 and abdomen. The brush of the false legs at the posterior 

 extremity is not so dense. The head is larger, more 

 elongate, thickened dorso-ventrally in the occipital region. 

 Dusky above on head and thorax. A pallid region about the 

 eye extends posteriorly on the side of the head and then 

 dorsally along the occiput. It is probably a Hydropsyche. 



Case-fly Larva No. 6. —Length of large examples 10 mm. 

 Pure white. No ventral branched appendages. Head large 

 relatively and elongate, yellow, the eye well forward just 

 posterior to bases of mandibles. A large white membranous 

 T-shaped expansion of the upper lip overlying the mandibles. 

 Dorsal plate of prothorax and legs pale yellow. Posterior 



