January 1S91.] 



PSYCHE. 



13 



vertical line ,* indicates the essential- 

 ly generalized and larval character 

 of the order, and does not necessarily 

 imply any nearer relationship to Neu- 

 roptera, which stands on the right, 

 than to Coleoptera on the extreme left. 

 The height to which the vertical bars 

 have been carried above the plate is a 

 rough approximation to the specializa- 

 tion attained by the adults, and also to 

 the removal of the mode of development 

 from the primitive Thysanuroid mode. 



The orders existing to-day are re- 

 garded as pai - allel series differing from 

 each other in structure, and not as yet 

 connected by well-known intermediate 

 forms. Where the probability exists 

 that certain orders have had a common 

 origin, they are placed on the same 

 radiating lines, as seen in Diagram III, 

 orders II-III ; also VI-VII, and VIII- 

 IX ; and this rule has been departed 

 from only where the data seemed to 

 justify a more natural interpretation, as 



in the case of the orders from XII to 

 XVI, inclusive. 



All of these graphic presentations 

 are necessarily extremely rough approx 

 imations to the actual facts, and present 

 even the authors' views in a very im- 

 perfect manner. Nevertheless, if con- 

 scientiously studied, they will, it is 

 hoped, help to give teachers some ideas 

 of the principles upon which a classifi- 

 cation is based, and prevent them from 

 falling into the absurd but natural mis- 

 takes often occasioned by the linear 

 treatment of types in the text. 



LIST OF ORDERS. 



DESCRIPTIONS OF THE LARVA AND PUPA OF SCOTOBATES 



CALCARATUS FABR. 



BY W1I. BEUTENMULLER, NEW YORK. 



Larva : — Head subquadrate, anterior angles 

 obtusely rounded, sides moderately rounded, 

 shining. Clypeus tranverse, about three 

 times as broad as long, oblique. Labium 

 smaller than the clypeus, anterior margin 

 rounded and beset with a few bristle-like 

 hairs. Antennae three jointed, first joint 

 cylindrical, about twice as long as broad; 



*See also the diagram given by Packard in Third 

 Rep. U. S. Ent. Com., 1SS3, p. 295. 



second joint considerably longer, clavate ; 

 third joint minute, cylindrical, with a few 

 hairs at the apex. Mandibles short, stout, 

 arcuate externally, excavate internally, apex 

 tridentate, base with a prominent elevation 

 with two small teeth. Maxillae subcylindri- 

 cal, stout, elongate, lobe somewhat truncate 

 at the apex with a number of bristle-like 

 hairs. Maxillary palpi three jointed, first 

 joint stout, cylindrical, broader than long; 



