72 



nllel the older and l)etter-known enemy of this staple. The adults, 

 larva3, pupa^, and eggs of this insect, together with canes showing 

 the larval burrows and containing the larvse, were transmitted to 

 Col. G. B. Brackett, pomologist of the Department, by Mr. B. Howell 

 Jones, of Georgetown, Demerara, who gave a rather interesting 

 account of it in a letter which is quoted l^elow. The insect proved to 

 be Castnia liens Fab., and the only known food habit hitherto re- 

 corded is the breeding of the larva^ in the Upper Orinoco in the roots 

 of an orchid. As shown in Westwood's Monograph of the genus 

 Castnia (Transactions of the Linna?an Society, 2d series. Zoology, 

 Vol. I, J). 173, 1875, and by Herbert Druce in his Lepidoptera- 

 Heterocera (Biologia Centrali Americana, Vol. I, p. 26, 1883), this 

 insect has been collected in Nicaragua, Costa Eica. Ecuador, east 

 Peru and Bolivia, Guiana, Trinidad, Amazons, and Brazil. Accord- 

 ing to Druce, it is a scarce insect in Central America, but seems to be 

 more abundant in its more southern range. 



The nuiterial sent by Mr. Jones was so ample and in such an 

 excellent state of preservation that it seemed worth while to have 

 careful drawings made, which are reproduced for this note. (PI. 

 IV.) The large size of this insect, in comparison with Diatrcea sac- 

 charalis^ commonly known in this country as the " larger cornstalk- 

 borer " to distinguish it from the smaller cornstalk-borer [EJasmo- 

 faljms lignosellus) , warrants the application of the term given at 

 the head of this article to this new cane pest. The assumption of 

 the cane-feeding habit by this insect is another illustration of the 

 sudden development of an injurious food habit in an insect Avhich for 

 years has had no economic importance, and shows how little can be 

 ]:)redicted of any insect from its known food habits. It is to be hoj^ed 

 tliat this insect will not develop a northern trend through the AVest 

 Indies as did its forerunner, the larger cornstalk-borer. The fact 

 that it is not especially abundant in its northern range in Central 

 America is an element of security, l)ut can not necessarily be relied 

 upon, because this scarcity may be due to a lack of suitable plants in 

 which it can breed. Mr. Jones's letter is a most interesting contri- 

 bution to the knowledge of the history of this insect, and it is signifi- 

 cant that now that it has found a food plant furnishing abundant 

 means of reproduction it breeds in enormous numbers. I quote the 

 letter referred to in full: 



Georgetown. Demerara, British Guiana, 



November 28. 190 Jf. 

 G. B. Brackett, Esq, 



Dear Sir: I am taking the liberty of sending you a small box containing the 

 eggs, caterpillars, chrysalis, and butterfly that has been doing some damage to 

 some of our cane fields. It is entirely nevA- to us here, though some planters say 

 they have seen it before, but they did not think it did much damage. In the 

 present case it is doing a great deal of damage, and a few children with nets 



