1869.] 171 [Minot. 



terminations of the nervures, except on the secondaries above. An- 

 tennas filiform, brown. Head, eyes and thorax, blackish brown; 

 abdomen above mouse-color, beneath, like the hind wings; femur 

 murinous; tibia black and white. Hind tibia with two pairs of spurs. 



This species is remarkable for imitating the markings of the rhopal- 

 ocerous genus, Chionobas, which occurs in the same locality. If we 

 follow Darwin, this fact maybe explained by supposing that the pecu- 

 liar moss-like markings serve to protect it from its foes by its close 

 resemblance to the bare or lichen-covered rocks among which it is 

 found. I am indebted to the kindness of Mr. Sanborn for specimens 

 of this interesting Geometer. His specimens were, I believe, all taken 

 in August, on the sides, and near the summit of Mount Washington. 

 I do not know of its being found in any other locality. Some of the 

 specimens were taken in a maple grove. One point is worthy of no- 

 tice : that where Chionobas has a white band on the secondaries, this 

 Anisopteryx has a dark one. 



Fidonia Faxonii Minot. The male of this species may be dis- 

 tinguished by the entire absence of the white markings of the female. 

 This species appears in August and September, not coming out until 

 the very last of the former month. My remarks on its appearance 

 and abundance apply to Fidonia bicoloraria Minot, but not to F. 

 Faxonii. 



Mr. W. H. Dall remarked that while passing over the 

 Portage to the Yukon River, in Alaska, when the tempera- 

 ture was below zero of Fahrenheit, he shot a Canada jay, 

 which had in its mouth the caterpillar of an Arctian ; after- 

 wards, when the thermometer was sixteen degrees below 

 zero, he found one of the same caterpillars crawling upon the 

 snow. On the middle of the frozen river, whenever the sun 

 shone for a short time upon the crust, he saw upon the snow a 

 species of Lepisma or Podura in great abundance, although 

 the cold was intense. The caterpillar of Vanessa Antiopa 

 was twice noticed alive during the winter, and the perfect 

 insect was seen at ISTulato, May 20th, when the nightly tem- 

 perature was below freezing. 



