OF WASHINGTON, VOLUME XVII, 1915 



153 



In their monograph of Larinus, Capiornont et Leprieur (Ann. Soc. 

 Ent. France, ser. 5, vol, 4, 1874, p. 65) give a full description 

 of Larinus nidificans Guibourt. They cite its origin as Syria 

 and Persia. The cocoon is said to taste sweet and to swell in 

 water without completely dissolving even after long boiling. 

 It contains 66 per cent of a substance similar to sago, a little 

 gum, a small amount of inorganic mineral matter, and 28 pel- 

 cent of the sugar called trehalose. The natives use it in a decoc- 

 tion against bronchial catarrh and as a food like tapioca. The 

 sago-like substance has been chemically named trehalum. It is 

 a tasteless carbohydrate, with the formula C 2 4H42O 2 i. 



A very concise summary is also given by Bargagli (Rassegna 

 Biologica Rincofori Europei, 1883-7, pp. 110, 111) of the habits 



n -^r v ?>> 1*1 



Fig. 1. Larinus nidificans. Pupal cells. 



of the weevil and of the nature of its cocoon. Bargagli cites 

 the names of the substance of the cocoons as thrane, thrale, trehala, 

 tricara and tricala. The cocoons are gathered before the weevils 

 mature. 



The specimens exhibited are the Lvriimx nidificans Guibourt 

 as denned by Capiomont and Leprieur. Fragments of tin- 

 plant were submitted to Mr. Paul C. Standley and determined 

 by him as a species of Echinops. 



The genus Larinus is confined in its habits to breeding on ( '<>m- 

 positse related to the thistle. The larva? usually feed at the 

 base of the flower head and then construct a cocoon (fig. 1) This 

 cocoon is made by abdominal excretion, and causes the larva to 

 diminish considerably in size during its construction. 



Gervais and Van Benedcn as well as other authors quote ( ierbi's 

 reference to the use of the larva? of Hfr/nuci/llus antiodontalgicits 



