LAEViE OF THE PEIONIN^. 11 



the ventral, the hypopleurum. Below the parascutal area is an 

 elliptical lobe bearing the spiracle, and posteriorly of this area and 

 reaching behind the ampulla is the postscutellum. All nine abdominal 

 segments bear a longitudinal lateral zone, which is swollen and very 

 distinct on the last three segments. Each lateral zone bears a 

 tubercle — the pleural tubercle — which bears several long setae and is 

 largest on the last three segments. On the lateral zone of the first 

 three, four, or six segments (according to the species) occurs a circular 

 or elliptical disc surrounding a deep pore. For this structure I 

 propose the name, the pleural disc.^ (Compare with Perris, Larves des 

 Coleopteres, 1878, p. 419.) 



The eighth and ninth abdominal segments are less differentiated 

 than the preceding. They bear neither dorsal nor ventral ampullaSj 

 but are uniformly smooth and undivided into areas. The ninth is 

 longer than any other abdominal segment; it is large and inflated, 

 and never deeply telescoped into the eighth as in the Cerambycinge. 



The tenth abdominal segment or anal lobe is situated directly 

 posterior, or dorso-posterior, to the ninth segment. Three sutures 

 divide it into three equiangular lobes — one dorsal and two latero- 

 ventral. Often the dorsal lobe protrudes beyond the others. They 

 are smooth or rugose according to the species. 



Between the segments are two ove:^lapping bands of skin, known 

 as intersegmental skin. This allows free longitudinal expansion and 

 contraction of the segments. In the thoracic segments this skin is 

 very narrow. 



The larval characters of the Prioninae may be briefly summarized 

 as follows: 



Head transverse, dorsal margins of epicranium behind front fused 

 for some distance, later separating, angulate (i. e., head emarginate 

 behind) . Inferior retractor muscles of head inserted in a deep fovea 

 before cervical foramen. 



Mandibles wedge-shaped, cutting edge broadly emarginate, apex 

 produced, acute. 



Epistoma produced in two triangular lobes or a dentate carina 

 over clypeus (except in Parandra) ; three epistomal setae on each side; 

 front produced over epistoma, dentate or carinate. 



Clypeus thick, trapezoidal, as wide at base as epistoma. 



Labrum broad, thick, semicircular or cordate. 



Maxillae movable; cardo distinct; maxillary sclerite ^ fuU, cush- 

 ioned; palpifer not distinct, smaU; lacinia borne on stipes. 



Antennae strong, partially retractile. 



Legs short, stout, conical. 



1 This disc has proved of great value in the identification of the larva in certain subfamilies of Ceram- 

 bycidae. The structure of the whole organ is interesting and will be the subject of a later paper. 



2 Kemner, A. Beitrage zur kenntnis einiger schwedischen koleopterenlarven. Amara simUis GylL, 

 Emus hirtus L., Creophilus maxillosus L. und Leistotro'plius murinus L. 31 p., 20 figs., 4 pi. (Arkiv far 

 zoologi, Bd. 7, heft 4, N:o 31), Feb. 12, 1913. 



