Vol. xxii] 



ENTOMOLOGICAL NEWS. 



449 



Studies on Costa Rican Odonata. 



III. Structure and Transformation of the Larva of Mecistogaster 



modestus. 



By PHILIP P. CALVERT, PH.D., University of Pennsylvania, 



Philadelphia, Pa. 



(Plates XVII-XIX) 



The early stages of this long-bodied dragon fly whose dis- 

 covery and habits have been described in the NEWS for Novem- 

 ber, pages 402-410, furnish the following 



DESCRIPTION OF THE LARVA OF M. MODESTUS. 



Material Studied : 



(a) From Juan Vinas, Costa Rica. 



(in fragments) 



101 ? larva recovered from crop of 

 No. i 



(b} From Orosi, Costa Rica, March, 1911, collected by Sr. C. Picado 

 T., and forwarded by Prof. J. F. Tristan. 



9 exuvia dimensions as above, 20.5 and 18 mm. 



$ exuvia dimensions as above, 23 and 19.5 mm. 



(f) From Cordoba, Mexico, April, 1908, bred by Mr. F. Knab. 

 (See Calvert, 1910.) 



9 exuvia (distorted). 



