406 THA.YSFORMATIO.VS OF INSECTS. 



There are several well-authenticated instances of bot flies 

 attacking men, but it is probable that th''=; is an accidental 

 occurrence, and that they are the parasites ot the monkey or 

 dog. 



The/e are some very extraordinary flies which inhab't the sea, 

 and Packard describes the larva of a species living on floating sea 

 grass. He noticed that they were transformed into pupae, and 

 that in nineteen days the second metamorphosis into the fly was 

 perfected. He also describes an Ephydr.i whose larva lives in the 

 strong salt works of Illinois and under the sea-weed on the shores 

 of Narragansett Bay. 



The Ticks are Diptera without wings, or which have them in a 



Mdopkagus ovis. LeptaLcna ceift. 



rudimentary condition. They have a sucker, and live parasitically 

 upon all sorts of creatures. 



The Sheep Tick, MelopJiagiis ovis, has a wingless and hairy 

 body and a long proboscis. The young are developed within the 

 body of the parent until they attain the pupa state, and then the 

 pupa in its case, which is nearly as large as the whole insect, is cast 

 forth. Packard notices the Bat Tick, which has a small body and 

 enormous legs, and it is either blind or provided with four simple 

 eyes. These insects are of small size, being only a line or two in 

 length. 



The Stag Tick, Lepiotoeiia cervi, like the Sheep Tick, has no 

 wings, and remains attached to the animal ; but some Bird Ticks 

 have very small wings, which enable them to leav^e one animal 

 for another. These degraded Diptera are the connecting links 

 between the true insects and the spider and mite families. 



