286 NOTES ON NATURAL HISTORY BOOKS. 



ejection of fluids is a natural plan of defence resorted to by several 

 animals of different classes : as, for example, by the Llama, Skunk, 

 &c., among the mammalia ; the Petrel and Vulture among birds ; 

 the Sepia among fishes; the Catchweed Beetle, (Timarcha tencbri- 

 cosaj, the Oil Beetle ( Proscarabwus vulgaris), the larvae of Centra 

 vinula, &c., among insects.* 



Of the hard cocoons of Trichiosoma lucorum, I have seen several 

 specimens ; and they are, as Mr. Curtis observes, pretty common 

 round London, on the branches of hedges. In what manner these 

 are formed, does not appear to have been discovered ; but, from ex- 

 amination, I am led to conceive that the ligneous materials (for of 

 such they seem to be constituted) are first masticated into a 

 paste, which is then spread into the required shape, its tenacity and 

 durability being, perhaps, obtained by the aid of a glutinous secre- 

 tion. When the insect has escaped from its cocoon, this exhibits 

 the appearance of a deep cup furnished with a round lid, the hinge 

 of which is so elastic, that the two parts are pressed so closely to- 

 gether, as to render the line of their division not at first very ob- 

 servable."t 



* " The larvae of this insect ( Trichiosoma lucorum J having been peculiarly 

 abundant this season, on all the Hawthorns around Dundee, I have had," 

 says Mr. William Gardiner, "an opportunity of observing their habits, and 

 can corroborate the curious fact of their ejecting from the pores of their bo- 

 dies, a liquid, in thin fountain-like columns, as stated by Mr. Fennell in the 

 Mag. Nat. Hist., vi., p. 157- * * * The doubt expressed in this 

 Work, vol. vii., 266, of this habit being usual to the species, has probably 

 arisen from the circumstance of its being manifested only during the earlier 

 stages of the insect's existence ; for, when the larvae appears in its last coat, 

 no trace of this habit remains. The fluid, which is of a green colour, and 

 strong disagreeable odour, is spirted with such violence, as often to force it 

 to the distance of more than a foot from the insect ; and its use is, perhaps, 

 to defend the larva, in its more tender state, from the annoyance of the Ich- 

 neumon flies. In the last stage of its growth, the head, which, in the pre- 

 vious stages, was black, is of a bright red colour, gradually softening into 

 yellow towards the sides ; and the body appears less mealy-like, but is thickly 

 covered with white transverse ridges. They feed only during the night, 

 and repose themselves, half coiled up, on the under sides of the leaves 

 throughout the day. They first made their appearance here, this season, 

 about the 22nd of June (1834), and in the beginning of August, were trans- 

 formed into pupae." — May. Nat. Hist., viii, p. 628. 



+ " I have found," says Mr. Gardiner, " the beautiful figure and descrip- 

 tion (of the cocoon), with which Mr. Woodward has furnished us in Mag. 

 Nat. Hist, v., 85, perfectly accurate, with the exception of his supposing it 

 possible that the fibrous appearance of it was owing, in part, to ' the agluti- 

 natcd hairs of the larva.' The larva, unfortunately, cannot apply its hairs 



