154 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



Gerbi, a species nearly related to Larinus, in certain parts of 

 France, for toothache and inflammation of the gums. Merely 

 touching the insect to the aching part was claimed to give relief. 

 This antiodontalgic property is also ascribed by Gerbi to various 

 other weevils, such as Rhynchites bacchus and R. betuleti, and 

 Larinus jaceae. 



Incidentally it may be stated that various authors cite the 

 fact that the larvae of the palm weevil (Rhynchophorus palmarum 

 Linnaeus) are considered a very delicious food by the natives in 

 Central America. The larvae are roasted and when properly 

 cooked are esteemed rich and delicate eating. There are also 

 suggestions in the literature as to the edibility of Calandra 

 chinensis. 



THE SECRETIONS EMPLOYED BY RHYNCHOPHOROUS 



IN COCOON-MAKING. 



BY FREDERICK KNAB, Bureau of Entomology. 



The question of the source of the substance constituting the 

 bulky cocoons of Larinus shown by Mr. Pierce is an interesting 

 one. There is good reason to believe that it is at least for the 

 greater part a product of the malpighian tubes, and therefore 

 voided through the anus. Moreover, it would seem that such is 

 the origin generally of the cocoons of very diverse structure and 

 texture constructed by the larvae of many genera of Rhyncho- 

 phora at the time of pupation. The viscous secretion covering 

 the bodies of certain externally feeding weevil larvae is undoubt- 

 edly from the same source. 



In the discussions of the biology of certain weevils one frequently 

 finds the statement that the larva "spins" the cocoon, the im- 

 pression conveyed being that the process is analogous to the 

 cocoon spinning of lepidopterous larvae. Indeed, labial spin- 

 nerets occur in some weevil larvae, 1 and it can not be altogether 

 denied that some of them "spin" in the restricted sense; but 

 this organ is very minute, so that its role must be a very sub- 

 ordinate one. It seems probable that the rectal glands contribute 

 also to the cocoon-forming substance, and possibly there is still 

 another contributing source, the surface glands distributed over 

 the body. Thus, the cocoon may be composed of material from 

 four distinct sources, just as Dr. Boving has demonstrated in 

 such an excellent manner for Donacia. 2 



1 Henneguy, L. F. Les Insectes, p. 462. 1904. 



2 Boving, Adam Giede, Natural history of the larvse of Donaciinaa. 

 Internat. Rev. d. gesamten Hydrobiol. u. Hydrogr., vol. 3, Biol. Suppl. 1, 

 108 p. ,7 pis. 1910. 



