1885.] NATURAL SCIENCES OF PHILADELPHIA. 103 



February 26, a younger specimen, about one-third grown, 

 hanging in a crevice in the site above described, when touched 

 and lightly pressed down, slowly moved its legs and began to 

 struggle back to its perch. The thermometer ranged from 20° 

 to 25° ; on the day before the range was from 21° at 7 A. M., to 

 28° at 11 A. M. 



During the six weeks over which these observations extended, 

 the temperature was unusually low for this vicinity ; for a great 

 part of the time, the thermometer stood below freezing point, and 

 several times reached zero. The month of March following was 

 unusually severe, the thermometer frequently reaching winter 

 temperature. On the first of April, however, the above-named 

 spiders, and others of a younger brood, were in their webs hale 

 and active, drawn out by the first soft days of spring. It would 

 seem, therefore, that the hibernation of spiders (of this species, 

 at least), is not accompanied with a great degree of torpidity; 

 that they preserve their activity and spinning habit while exposed 

 to cold ranging from freezing point to zero (Fahrenheit) ; that 

 after long and severe exposure, the recovery of complete activity 

 when brought into a warm temperature is very rapid, almost 

 immediate ; and that on the return of spring, even after a pro- 

 longed and severe winter, they at once resume the habits of their 

 kind. 



In all the above specimens the abdomens were full, indicating 

 perfect health. Other spiders hung upon their webs with shriv- 

 eled abdomens, quite dead, among them one of his specimens, a 

 male, who died during the course of the observations. A Pholcus 

 phalangioides hung thus dried up, holding with a death-grip to 

 her web b} r the two fore-pairs of legs which supported the cephalo- 

 thorax in a position parallel to the plane of the horizon, while 

 the long abdomen hung down at right-angles thereto, and the 

 third and fourth pairs of legs were drooped downward and back- 

 ward. He could not determine that these and other spiders 

 perished by the cold. The living individuals were all characterized 

 by the plump abdomen, as though there had been little or no ab- 

 sorption of tissues for nourishment of life. There appeared to 

 be no growth during hibernation. 



The same facts hold good as to the winter habits of Orb- 

 weavers. The young survive the winter in the admirably ar- 

 ranged cocoons provided by maternal instinct. But earl}' in the 

 spring many adults of both sexes are found nearly full-grown, 

 who have also safely weathered the cold months. He had, at 

 various times in midwinter, collected examples of Epeira strix, 

 and had found the species adult in spring. Specimens of Strix 

 may be frequently taken during the winter months from rolled 

 leaves, within which they have weathered our hard frosts. These 

 rolled leaves also serve for nests during summer. Dr. Geo. Marx 

 had informed him that, on the capacious Government grounds in 



