411 



With this view a lono; tendril was bent at an anffle of 60 

 degrees around a stake placed midway in length, and was con- 

 fined in this position by a second stake placed near its curving 

 end, and in contact with the opposite surface. 



Soon after this adjustment was made the free curved extremity 

 began to close upon the stake. In twenty-four hours this end had 

 made two and a half turns around the stake, and the portion be- 

 tween the two stakes had begun to twist, but no spire had yet 

 formed. The day following it showed an imperfect open spire, 

 and on the third day it had formed two strong coils adjoining each 

 of the stakes, the turns as before being oppositely directed, and 

 having a nearly straight segment between them. 



4. In many cases the motion of the curving end of the ten- 

 dril was sufficiently rapid to carry it through a sensible angle in 

 the first five or ten minutes. Even when the tendril appeared 

 quite unimpressible when thus watched, it was usually found by 

 the next day to have moved through a considerable space. This 

 capacity of motion would seem to be greatest at a particular stage 

 of growth and afterwards to decline. 



The following experiment exemplifies the great activity of the 

 tendril in favorable circumstances : 



A tendril four inches long, which had bent itself into a wide 

 hook at the free end, was brought in contact by its concave sur- 

 face with a smooth, round stake, leaving about three-fourths inch 

 of the outer part of the hook projecting on one side. The coil- 

 ing action began at once, and could easily be followed by the eye. 

 In fifteen minutes the outer part of the hook had worked through 

 half a circle, and the stake was clasped in a close coil. 



OBSERVATIONS ON THE HABITS OF A SPECIES OF HORNET 

 ( Vespa), WHICH BUILDS ITS NEST IN THE GROUND. BY 

 PROF. JEFFRIES WTMAN. 



The colony of hornets which is the subject of the following 

 observations, was first noticed towards the end of August, while 

 they were making a nest in the slope of a bank in Cambridge. 

 The process of excavation was still going on, as was obvious from 

 the fact that each worker came out with a pellet of earth in its 

 jaws. As long as they were not interfered with they allowed any 

 one to approach quite near to the nest and watch their movements 



