﻿10 NINTH ANNUAL REPORT 



declares that the female ruptures, with her weak saws, the epidermis 

 of the leaf-ribs, and thus brings the surface of the egg in very close 

 connection with the exposed parenchyma.* 



He further remarks that the rupturing or scratching (Verlet- 

 zung) which Nematus t'e:Mi!/-icosw-s causes in ovipositing is "probalbly 

 confined to the epidermis and may therefore be easily overlooked." 

 This may account for the fact that Mr. Saundersf states, after carefully 

 looking into this matter, that he is fully satisfied that the eggs are not 

 embedded in the leaf tissue at all, but fastened very slightly to the 

 surface. Upon subsequently questioning Mr. Saunders more particu- 

 larly about it, he wrote (May ^5, 1874) : ''Whatever Siebold may say, 

 I cannot help. My microscope does not show me the egg as pushed 

 through the epidermis — it appears distinctly on the surface — it is very 

 different from the Rasberry saw-fly in this respect." Dr. A. S. Pack- 

 ard, Jr., also states {Emhryological Studies in Mem. Peabody Ac. of 

 •Sc, Vol. 1, No. 3,) that the eggs are simply glued to the surface, and 

 this is the experience of all other American writers on the subject. 

 The investigators named are all most careful observers and good 

 microscopists ; yet either there is error somewhere, or else, which is 

 an interresting possibility, the insect has been modified in habit since 

 its introduction to America. 



While in the majority of cases in America, as observed by Saun- 

 ders and Packard, the abortive saws of the female may not rupture 

 the epidermis; in some cases, however, they certainly do; for in moat 

 but not all the specimens which I have examined, I have detected the 

 slight rupturing mentioned by Siebold. It is still plainly discernible 

 in a dried leaf now before me from Mr. J. A. Lintner, of Albany, N.Y., 

 and yet containing well formed eggs that were parasitized. Never- 

 theless, when made, it is so slight as to be altogether insufficient to 

 support the egg without the adhesive fluid that accompanies it. The 

 •eggs, while attached, appear no more inserted than are those of the 

 genus Lyda^ and differ materially in this respect from those of all 

 other Saw-flies known to me. 



Siebold himself remarks that there can be, with such slight 

 skinning of the epidermis, but little vital intercourse between the egg 

 and the plant, and the facts that I have recorded as to the swelling of 

 the eggs of our Katydids when fastened to perfectly dry and dead 

 substances (Rep. V, 124,) would indicate that the swelling is not due 

 solely to endosmosis from the attached parts of the plant, but depends 

 on another principle, difficult to analyze, but evidently more or less 

 atmospheric. 



•Beitr. zur Parthenogenesis der Arthropoden, 1871, p. 123. 

 iAm. Entomologist II, 274 ; Can. Ent, II, 112. 



