20 



northern specimens. It is doubtful if any more valid distinction than 

 this very common climatic variation exists between the two species of 

 Amphizoa now in onr catalogue. The form jo*<?2>/rJ has long ago been 

 recognized as having no specific value. 



Thelarva of Amphizoa (Fig. 5) is a short-legged, compactly built insect 

 aboutthree-qnartersof an inch in length, of an umber-brown color vary- 

 ingto nearly black. The upper surface is convex and strongly chitinized, 

 showing cloudy mottlings, which arrange themselves in longitudinal 

 lines, and in dark specimens disappear, leaving several rows of trans- 

 lucent dots and dashes more or less sharply defined. The under sur- 

 face is quite flat and naked. The dorsal shields entirely cover the up- 

 per surface of each segment and extend outward on the sides, forming 

 explanate lobes. These lobes, evenlj- rounded on the throax, grow 

 more and more acute posteriorly, and their outer margins give a 

 remarkably regular fusiform outline to the body, which terminates 

 acutely behind. The head is large and prominent, with a group of six 



Fig. b.— Amphizoa Iccontei: larva, enlarged; a, dorsal view: c. ventral 

 parts, much enlarged (original). 



'w ; h. head, showing luoiUh- 



ocelli on each side near the front angles. The antennae are short, 

 three-jointed, placed just behind the jaws on the side margins. The 

 jaws are deeply channeled within and armed with minute denticula- 

 tions on the lower cutting edge. The buccal cavity is large, adapted 

 to the mastication of food, and provided with molar plates formed by 

 thickenings of the inner surface of the clypeus above and the mentum 

 below. The maxillfe are stout, basal pieces surmounted by four-jointed 

 palpi and the two-jointed inner lobes. The under lip is broadly trans- 

 verse and prominent, without ligula, and with short, two-jointed palpi. 

 The legs are widelj^ separated, with six articulations, including the 

 double claws. The abdomen consists of eight segments, and terminates 

 in a pair of .short movable spines which enter the eighth segment from 



