101 



THERE ARE SEVERAL DISTINCT SUGAR-CANE BORERS. 



Ever since Giiildiiig described his Diatnca fiaccJiari, nearly all cranibid 

 borers in suj?ar-cane have been assumed to be identical with this species. 

 I assume that Guildiuj^'s insect mny b«* identical with <mr Louisiana 

 borer since it is West Indinii, and is likely to have been introduced 

 into Louisiana with seed cane. I can not, however, consult the descrip- 

 tions of (Tuilding- as his work is inaccessible. There are no salient 

 points which would readily <listingiiish the moth or the pupa in a brief 

 or a popular description ; but the larva is rather peculiar among the 

 Crambida'. The ordinary form in corn (Fig. 4, a) when fuU-gnnvn is about 

 25 millimeters long, stout, 5 millimetres in diameter, an<l of the ordinary 

 subcylindrical form. It is dirty white in color and is jn-ofusely spotted 

 with black or brown, the ordinary piliferous spots being large and dark 

 colored. They are arranged about as in the larva of HeUothis armif/era. 

 The anterior dorsal spots of the last two thoracic and tirst seven 

 abdominal joints are 

 large and round, those 

 on tlie eighth and 

 ninth abdominal joints 

 being confluent (Fig. 

 4, e). The posterior 

 dorsal spots are more 

 widely separated, are 

 transversely elonga- 

 ted, and become con- 

 fluent, forming a band 

 on the second and 

 third thoracic ioints 

 (Fig. 4, d). The head 

 and thoracic jdate are 



honey yellow. There Fig. i.—Diatrceu naccharaUs .- o, b. c, varieties of larva enlarged ; rf. 

 is considerable Varia- third thoracic segment; f, eighth abdominal segment ;/. ahdouiinal 

 ,. . , . _ ,, ■. segment from side ; <7, same from above— still more enlarged (origi- 



tion m the size of these nai). 



spots, and in some individuals they are comparatively small, while in 

 others (alcoholic) they are so large as to give the whole larva a brownish 

 eftect. There are ti^equently in the alcoholic specimens two subdorsal 

 puri)lish longitudinal lines, and the head and prothoraiiic plate vary 

 fi'om briglit honey-yellow to brown. 



The Mauritius larva is described by Westwood as follows: 



The caterpillar has the head covered with a black plate, and the neck is also cov- 

 ered with a paler colored plate, and the body is fnruished with a number of short 

 black hairs arising from small black points connected laterally by a pink band. 



This descrij)tion shows the Mauritius species to be difterent from ours, 

 and presumably from the West Indian form. 



Fabricius's description of the larva of the South American species is 

 as follows : 



