SCHISTOCERCA, SPHINGONOTUS AND HALMENUS 439 



ferentiated into the two species. Finally, by migration to the other 

 islands — from Chatham to Indefatigable and Albemarle, and from 

 Charles to Hood, Harrington and Indefatigable, the various races 

 could have been produced. 



DETAILED DESCRIPTIONS. 



SPHINGONOTUS TRINESIOTIS sp. nov. 

 Distribution. — Chatham, Indefatigable and Albemarle Islands. 

 The characters of its three varieties are as follows : 



SPHINGONOTUS TRINESIOTIS CHATHAMENSIS var. nov. 



From Chatham Island. 



Description of the Type. Male. — Head pale clay-color, front 

 clouded with minute dark punctations ; gence paler than the other parts : 

 a black post-ocular stripe, with a narrow, pale longitudinal line above 

 it. Dorsal surface of prozona same color as top of head ; doi'sal sur- 

 face of the metazona dusky reddish-brown with a pale stripe on each 

 side, continuous from the pale clay-color of the dorsum of the prozona, 

 running outward and backward just within the angle of the lateral 

 deflection of the metazona. Just below the lateral angle of the pro- 

 zona, bordering the pallid dorsal area, a dusky stripe continvious with 

 the post-ocular stripe of the head ; below this a pale area, and below it 

 a wide reddish-brown band inclined obliquely from behind, forward 

 and downward ; on the metazona this is continued less distinctly, with 

 an inclination in the opposite direction, exactly as in S. trinesiotis 

 indefatigabilensis; the upper stripe continues more faintly upon the 

 metazona, bordering the pale upper lateral stripes ; metazona between 

 these two black stripes reddish-brown; both prozona and metazona, 

 below the lower stripe, pale. Sides of mesothorax and metathorax 

 pale clay-color, clouded with dusky. Lower surface of the thorax 

 uniform pale yellowish. Prothoracic and mesothoracic legs pale 

 reddish-brown with a few dusky spots. Metathoracic femora very 

 pallid, each crossed externally by two oblique black areas which do not 

 quite reach the lower lateral outer carina, the latter with five small 

 black spots ; posterior swelling of femur slightly more brownish than 

 the rest ; on the inner surface the large spots well marked, the lower 

 part of the first running forward as a wide band to the anterior end of 

 the femur; no ventral femoral stripe. Hind tibia black at the upper 

 end, then surrounded by a short yellow band widest on the outer side, 

 from this to the lower end continuously bluish-brown, darkest on the 

 inner side ; spines yellow basally, black-tipped. First two joints of 



