NESTS OF THE ICAEIA. 491 



" Iu their disposition like the rest of the Vespiclae, they fly 

 with one accord to attack the intruder ; although their sting was 

 not very sharp, and nearly resembled the prick of a fine pin, 

 and was in a great measure deficient in the burning feeling- 

 experienced when stung by their brethren the Polistidte." 



The reader will doubtless notice the remark made in the 

 second paragraph, namely, that the cells are beautifully regular, 

 being perfect hexagons. This one fact entirely disposes of two 

 theories which at one time were generally entertained respecting 

 the hexagonal form of the bee-cell. One theory was, that the 

 cells were originally cylindrical and became hexagonal by mutual 

 pressure ; and the other, that they were made nearly solid at 

 first, and were scooped out so as to assume the hexagonal form. 

 In the case of the Icaria, however, neither mutual pressure nor 

 scooping is possible, and yet we find the cells as perfect hexa- 

 gons as those of the bee, or the common wasp, or the hornet. 



Begarding the species which is represented in the illustration, 

 Mr. Home writes as follows : — 



"This insect in its habits resembles Icaria varicgata. It 

 feeds its larvre with ejected juices ; hence one never finds any- 

 thing but the egg slightly attached to the bottom of the cell, 

 or the more matured grub, which spins itself a silken cocoon 

 over its cell with which to change to a perfect insect. It asso- 

 ciates in very large parties, and is extremely vicious when 

 disturbed, and flies at the party interfering with it, hardly ever 

 failing to sting him. The pain of the sting resembles burning ; 

 and in one case of my taking a nest, when I was severely stung, 

 the pain lasted for four days. I mention this, as it is curious 

 to observe the different degree of virulence of the poison of the 

 various small insects of this class. 



" The cells extend in masses of great size, and are placed in 

 the midst and amongst the twigs of thick garden bushes. I 

 also believe, from what I have seen, that the comb of one season 

 is not used in another ; perhaps it becomes weather-worn and 

 incapable of proper repair. This insect also has, like the Icaria 

 variegata, a retractile body, and its cells are beautifully regular 

 hexagons. It is much molested by a small class of moths 

 (Tineidae), and also by an Anthrax. In fact, the nest lies very 

 open to the attacks of parasites, who, as a rule, care nothing for 

 the sharpest stings. 



