184 LEPIDOPTERA OF NORTH AMERICA. 



in front, and tapering moderately on the sides to the head. The 

 abdomen is tapering and cylindrico-conlcal, at least twice the 

 length of the thorax. The wings are long, entire ; the anterior 

 rather broad across the inner angle, which is dilated, the hind 

 margin obliquely convex, sometimes slightly wavy, and the interior 

 margin with a long concave excision. The legs are long and 

 strong, the posterior tibice having four very long spurs. 



This group is very closely allied to Sphinx by the characters of 

 the perfect insect, and I have hesitated much whether to restrict 

 its limits as described by Mr. Walker, or to extend it. The gene- 

 ral agreement in the length of the tongue of such individuals here 

 included as I have been able to examine, has led me to take the 

 latter course. This will doubtless be regarded as objectionable, 

 but I think a greater degree of clearness of arrangement is 

 attained. Under any arrangement portions of the two groups as 

 compared to each other do not present well-marked or decided 

 differences, and if some of the members of the present one strongly 

 recall that of Sphinx, one member of the latter reproduces in its 



structure most of the peculiarities of Macrosila. 



Clemens. 



1. M. collaris Walker, p. 201. 



'Hoary, white beneath. Thorax dark-brown in front, and with 

 some brown marks on each side. Abdomen with a much inter- 

 rupted, middle, brown line, and with transverse, brown spots along 

 each side. "Wings brown beneath. Fore wings with a white dis- 

 cal dot, and with oblique, undulating, transverse, brown lines ; also 

 W'ith a testaceous streak which extends from the base to an oblique, 

 undulating, testaceous band. Ilind wings brown, whitish at the 

 base and along the anterior border, and with two hoary bauds. 

 Length of the body 18 — 19 lines ; of the wings 42 — 46 lines. 



West Indies. 



Clemens. 



2. M. hasdrubal Cramer, pi. 24G, f. F. 



Somewhat hoary. Head and thorax grayish-brown, the latter 

 with a black streak on the upper edge of tegulte. Abdomen with 

 indistinct, lateral, blackish patches, edged before with whitish. 



