OF PHILADELPHIA. 35 



Cabinet of tlie Academy. 



Ohs. From this description we may gather the facts, that the 

 larva in question corresponds with that of CE. hovis in being 

 destitute of hooks or holders at the mouth, but it widely differs in 

 general form, as the larva of hovis is oblong-oval, hardly more 

 narrowed at one end than at the other. The appearance of the 

 series of minute hooks which subserve the functions of feet, in 

 the latter species ; also are very different from that of the cor- 

 responding armature of this larva, the superior line of each 

 double series being narrow, and seemingly composed of but a 

 row of hooks, whilst the inferior line is much more dilated, and 

 the hooks far more numerous than in the superior line ; indeed, the 

 series of hooks of the South American larva are more like those 

 of the larvae of (E. eg'jw and hsemorrhoidaUs, than those of the im- 

 perfect bovis or ovis. But independently of those considerations, 

 the single character of the much attenuated form of the anterior 

 [posterior] part of the body of this larva, at once and eminently 

 distinguishes it from any [ 358 ] other yet known in this family j 

 while at the same time, the above description, taken in conjunc- 

 tion with its habitat, forbids the supposition of its belonging to 

 any other group, and will, I think, justify the restoration to its 

 place in the system of the Linnaean CEstrus hominis. To which 

 of Latreille's recently established genera it belongs, is at present 

 impossible to determine, though, for the present, it may, perhaps, 

 be not unsafe to refer it to the Cute[^i-e]bra* of Clark. 



Since the above was read to the Academy, Dr. Harlan has 

 furnished me with the following interesting extract of a letter, 

 which he received from a gentleman from whose leg this larva 

 was extracted : — 



"After a very sultry day's march, and being very much fa- 

 tigued, I went to bathe in the Chama, a small stream emptying 

 in the lagoon of Maracaibo. Not long after coming out of the 

 water, I received a sting from some insect, in the left leg, over 

 the upper and fore part of the tibia ; it was several days attended 

 with a considerable degree of itching, but without any pain, and 

 I continued on my journey some few days longer without ex- 

 periencing much inconvenience, except during several periods of 



* Weidmann in a letter states to me his preference of the term Try- 

 poderma for this genus. 

 1822.] 



