28 



The egg. — The egg is soft and delicate, and when dissected out 

 appears to be rather variable in shape, but the normal outline seems 

 to be elliptical oval, those deposited on the outer surface being inclined 

 to reniform and narrowed at one end. It is somewhat flattened on its 

 lower surface. Its length is nearly twice the width, the color limpid 

 whitish, surface moderately polished, with no apparent sculpture. 

 Eggs that were measured two or three days after deposition were 

 about 0.7™"' in length and a little over half that in width; some, how- 

 ever, were much shorter in proportion to the width. The membrane 



of the epidermis protecting the ^^^ 

 on the lower surface of the leaf, 

 although thin, does not permit a 

 good view of the o,^^ within. There 

 is little doubt, however, that the 

 eggs of this species, like those of 

 other sawflies of similar habits, in- 

 crease in size soon after they are 

 laid, b}" the absorption of nutriment 

 through their membranous skins' 

 from the vegetable juices which 

 surround them. 



Eggs are laid singly, but it could 

 not be ascertained whether only one 

 or two are deposited noi'mally on a 

 leaf at one time, although many are 

 often found on a single leaf. These 

 may be deposited b}' difi^erent fe- 

 males or by the same individual on 

 difl'erent visits. 



In figure 8 the ^g^ cells with 

 the slits made b}^ the female in ovi- 

 position are shown on the upper 

 surface of the leaf at f/, natural 

 size, and much enlarged at a^. The 

 under surface of the cells on the 

 lower surface of the leaf are shown 

 natural size at (6, and enlarged at //. 

 These illustrate the method of escape of the .vpung larva from the egg 

 The Qgg is shown much enlarged in outline at c and in section In sit 

 at d. 



DESCRIPTIONS OF THE LARVA AND PUPA. 



The loss of the material under observation through failure of the 

 eggs to hatch prevented detailed descriptions of the various stages. 



TJie newly-lidtched hirra. — The larva when first hatched presents the 

 appearance shown in figure 8. At f is shown at the right a larva 



Fig. 8. — Emphyftts canadensis — Violet leaves 

 showing nature of attack and the following: 

 a, egg cells on upper surface of leaf; Oi, an 

 egg cell magnified; b, cells after escape of lar- 

 vse; 6i, one of same magnified; c, egg from 

 above; d, egg in situ from side; e, female at 

 rest on leaf; /, newly hatched larvee on leaf; 

 /i, same enlarged; g, active stage of larva; 

 h, full-grown larva feeding, a, h, ej, (j, h, natu- 

 ral size; a^h, c, d,f^ , more enlarged (original ) . 



