150 STATES OF INSECTS. 



it is more probable that it secretes some other kind of 

 fluid, and is connected with defence. 



The singular organ in a similar situation, evidently 

 for that purpose, with which the puss-moth endeavours 

 to annoy its assailants, has been described in a former 

 Letter, to which I refer you a . Bonnet, who was the first 

 that discovered this organ, ascertained that it might be 

 cut off without injury to either larva or imago. He also 

 remarked in a caterpillar found in the wild succory (Ci- 

 chorium Intybus) another short, black, needle-shaped or- 

 gan between the conical part just described and the un- 

 der-lip b . De Geer mentions a remarkable fleshy horn- 

 like style, which issues from the lower side of the first 

 segment, between the head and the legs of the case-worms 

 (Trichoptera) : he does not describe it as retractile, or it 

 might be regarded as analogous to those of Lepidoptera 

 similarly situated, that I have just noticed c . In that of 

 the emperor-moth (Saturnia Pavonia\ there are perfo- 

 rated tubercles, which when the animal is molested spirt 

 forth a transparent fluid d . 



The horn-like appendage of the puss-moth (Centra Vi- 

 nula) is situated at the tail of the insect, and is composed 

 of two distinct cylindrical diverging branches, each about 

 four lines long, not united at the base. Each of these is 

 hollow, and includes a smaller cylindrical piece, which 

 can be protruded at pleasure, and withdrawn again, as a 

 pencil within its case ; or, rather, as the horns of a snail. 

 The two outer horns are tolerably firm, moveable at their 

 base, and beset with black spines ; the interior tentacula 

 are fleshy, moveable in every direction, and in full-grown 



* See above, Vol. II. 251—. »> Bonnet ii. 88. 



c De Geer ii. 507- 1. xi./. 16. c. * Ros. iv. 162. 



