SOCIAL INSECTS. 645 



which may be central or wholly lateral. Usually a varnish is 

 rubbed on the cells to prevent them being wetted by rain (Fig. 1). 



The envelope of a typical cardboard-maker (Chartergus char- 

 tarius) is of a veritable cardboard, white, gray, yellow, or buff in 

 color, smooth and solid, and impervious to the weather. It may 

 be conical, cylindrical, almost globe-shaped, straight, but more 

 often is a little curved. In the interior the platforms of cells 

 differ from those of the common paper- making wasp in stretch- 

 ing right across like so many floors, being fastened on all sides to 

 the walls. A simple hole perforates each, enabling the wasps to 

 get from story to story. The form arises from the mode of en- 

 largement of the dwelling. When the number of inhabitants be- 

 comes great and a fresh series of cells is required, these wasps do 

 not, as a preliminary proceeding, amplify the envelope so as to 

 extend the tiers ; they first build cells, and cover them afterward. 

 Beginning with the bottom of the nest, they set cells upon it, then 

 lengthen the outer wall so as to include this fresh stage, and close 

 in the end with a new floor, in its turn to become the ceiling of 

 the next tier of cells when enlargement is again desired. No 

 trace of the addition is suffered to remain and mar the covering, 

 which would seem constructed at one stroke. Probably these 

 wasps, like Myrapetra scutellaris (see Fig. 2), deviate from the 

 ordinary habits of wasps in being collectors of honey. 



It would be difficult to find a more peculiar nest than that of 

 Myrapetra scutellaris. It is huge as compared with the insects, 

 its brown cardboard wonderfully thick, hard, firm, and coarse in 

 texture, and composed, not of wood fibers, but of the dung of the 

 capincha, an aquatic cavy. The strange, fairly conical knobs that 

 beset the surface of the envelope may defend the abode, which 

 hangs low, against mammalia, such as tigers, jaguars, and cou- 

 gars, that would plunder it of its honey ; they appear to protect 

 and conceal the entrance ways of which, opposed to the custom 

 of wasps, there are many but they may be simple freaks of Na- 

 ture. It seems odd for beings so sensible to put these projections 

 on the end of the nest, no less than on the sides, necessitating 

 their gnawing them away each time they add a stage ; but prob- 

 ably they possess some means of softening the cardboard, and 

 doubtless the same material, worked up afresh, helps to estab- 

 lish the new tier and the new cells. 



It is represented in a bulletin of the Department of Agriculture that 

 about two hundred and fifty thousand cocoanut palm trees of all ages are 

 growing on the eastern coast of Florida, about twenty-five thousand of 

 which are bearing. The tree is fruitful near the salt water, but does not 

 thrive when removed inland. It begins to fruit in from five to seven years 

 after planting the nut. 



