388 



DIPTERA. 



towards the tips of the joint, and the hind tarsi are a little 

 dusky. Its length is .10 of an inch, not including the an- 

 tennae. It may be called the Mycetobia sordida. 



PULICIDJE Westwood. While this group has been considered 

 by many writers as forming a distinct " order," or suborder of 

 insects, equivalent to the Diptera, under the name of Aphanip- 

 tera, we prefer, with Straus Durckheim, to consider them 

 as wingless flies, and perhaps scarcely more abnormal than 

 Nycteribia or Braula. Instead of placing 

 them at the foot of the suborder, we prefer, 

 in accordance with a suggestion made by 

 Haliday (Westwood, Class. Insects, vol. 

 ii, p. 495, note), who places them near the 

 Mycetophilids, or "fungivorous Tipulids," 

 to consider them as allied to that group. 

 The body is much compressed ; there are 

 two simple eyes which take the place of the 

 compound eyes, the epicranial portion of 

 Fig 309 {. ne h ea( | being greatly prolonged, while the 



lab rum is wanting, and the labium is small and membranous ; 

 the four-jointed labial palpi, always absent in other diptera, 

 are long and slender. The form of the larva, including the 

 shape of the head and its habit of living in dirt, and its way 

 of moving about, as also its transformations, certainly ally the 

 flea with the Mycetophilids. 



We have received from Dr. G. A. Perkins of Salem, the eggs 

 and' larvae of the species infesting the cat, from which we have 

 also hatched the young larvae. The eggs (of which, according 

 to Westwood, eight or ten are laid by one female) were shaken 

 from the cat's fur, whence they are said to fall upon the floor 

 and there hatch, the larvae living in the dust and dirt on the 

 floor, and feeding on decaying vegetable substances. The 

 egg is oval cylindrical, and one forty-fifth of an inch long. 

 The larva when hatched is .06 of an inch long (Fig. 309, the 

 larva four days old ; a, antenna ; &, end of the body) white, 

 cylindrical, the sides of the body being a little expanded, 

 giving it a slightly flattened appearance when seen from above. 

 The segments are rather convex, the sutures being deeply im- 



