304 



Pig. 09.— Youus larva 

 from below — greatly 

 enlarged (after 

 Kiley). 



of Corylophus; the stipes well developed, and bi-articulate. Horn could 

 not entirely make out the niaiulibles as described by Le Coute, and 

 rather concluded that wliat Le Conte described is 

 really one of the granules which occur behind the la- 

 brun]. He considered that the piece could hardly be 

 even an aborted mandible, because of its diminutive 

 size. 



What all authors have agreed in calling the mentuni 

 is very noticeable, being large and broad, and trilobed 

 behind. The maxillse are strong, with complicated 

 stipes, and with two flat thin lobes, the inner one 

 smaller than the outer and rounded at the tip, both 

 lobes being ciliate. The maxillary palpi are four- 

 jointed, the labial jialpi three-jointed. The prosternum 

 is very large, subtriangular, concealing the insertion of 

 the coxfB, and extending over the front part of the 

 mesosteruum, as does this over the front of the meta- 

 steruum. Six ventral segments of the abdomen are 

 visible behind the posterior coxae, which conceal two 

 and the base of a third. The coxse are flat and not 

 at all i)rominent. The legs are characterized by broad 

 and flattened tibife and femora, and the strong spines 

 with which they are armed. The tarsi are five-jointed, 

 the front and middle pair with a row of claviform membranous append- 

 ages each side, which Le Coute fonnd only in the male. 



American entomologists have been satisfied to follow Le Conte and 

 Horn as to the position of Platypsyllus. Yet with such diversity of 

 opinion on the subject among high European authorities the importance 

 of a knowledge of the adolescent states has been recognized, as the 

 character of either the larva or pupa would settle the question. 



During a stay at West Point, Nebr., in Uctober, 1880, I learned from 

 one of my agents, Mr. Lawrence Bruner, that there was a beaver in a 

 creek not far from that point, and I at once made arrangements for him 

 to trap the beaver, and to look particularly for living specimens of Platy- 

 psyllus on the skin, and especially the earlier stages. He succeeded in 

 capturing the beaver and sent me some fifteen specimens of the larva 

 and also some imagos, but neither eggs nor pupre were found. A glance 

 at the larva satisfied me at once of its coleopterous nature; but as we 

 have, waiting to be worked up and published, an emharras de richesses 

 entomologiques in the collections of the National Museum, and as cir- 

 cumstances largely decide the precedence, I should probably not have 

 called attention to this larva for some time, had it not been that at the 

 last monthly meeting of the Entomological Society of Washington, Dr. 

 Horn, who was present, announced the finding, the present spring, by 

 one of his correspondents, of this very larva, and exhibited a specimen. 

 Some points about it, and especially the position of the spiracles, being 



