Psalis, as represented by its type americana, has the following 

 characters to contrast witli those of Labidura. The short heatl, as 

 pointed out by Serville, is more convex above ; the antenna; are com- 

 posed of fewer joints; the basal joint of the antenna; is longer and 

 slenderer, and increases more gradually in size toward the apex; the 

 pronotuin is nearly as wide as the head ; the prosternum broadens 

 greatly and regularly in front of the legs; the legs are scarcely so 

 slender nor so compressed; especially the fore femora are stouter; 

 the abdomen of the female does not taper at the extremity, the last 

 dorsal segment being quadrate, nearly as long as broad, and scarcely 

 narrower behind than in front ; while in Labidura it is transverse, 

 nearly twice as broad in front as long, but scarcely broader behind 

 than its length ; besides, the penultimate ventral segment of Psalis $ 

 leaves the sides of the last segment largely exposed ; and the last 

 segment itself is parted widely in the middle, while that of Labidura 

 is entire. The forcej)s of the ? are much stouter in Psalis than in 

 Labidura. Since writing the above, I find that Burmeister (Germ. 

 Zeitschrift Ent., ir, 82) has already remarked that if genera are to 

 be separated modo Serinlleano, americana and riparia (ffigantea) must 

 be placed apart. 



The species of Psalis occur in the tropics of both worlds. 



PYGIDICRANA. 



183L Serv. , Ann. Sci. Nat., xxir, 30 : proposes this name for the 

 single species v-nigrum (from Brazil) which thereby becomes 

 the type. 

 It has since been used by L-erville, Burmeister, Stal [Pydicrana] 

 and Dohrn in the same sense, each adding other species. Agassiz 

 (Nom. Zool.) proposes Pygodicrana as a more correct form of the 

 word {Tzuyrj, dixfi'jf/tr/). Burmeister (Germar Zeitschr. f. Ent., ii, 

 79) sug'^ests that Dicranopygia would have been better. The ge- 

 nus is moderately rich iu species, most of which are found in the 

 tropics of the Old World, including Australia; but two or three spe- 

 cies are found in northern S. America. 



PYRAGRA. 



1831. Serv., Ann. Sc. Nat., xxii, 34: founds this genus upon the 

 single species /areata (from Cayenne), which is therefore the 

 type. It is again employed by the author in his later work 



