66 THE CANADIAN ENTOMOLOGIST. 



this insect enters the gallery to place an ovum upon, or in direct contact 

 with, the host-larva, unless it waits until the doorway is made for the 

 moth's exit, for the ventilating orifice is too small to permit it to enter. 

 There is a period of several days between the making of the door and the 

 final ecdysis, when the larva is less active and shrinking for the change, 

 and which render it especially vulnerable, and it is believed this is the 

 time of attack True, the ovum of the Ichneumon might be merely thrust 

 within the ventilating opening, and the larva yet reach its host from this 

 proximity. If the above supposition is correct, there would be a period 

 of four weeks for the developments, and this seems sufficient. 



I am indebted to Mr. |. C. Crawford, of the U. S. National Museum, 

 for the determination of these Mymenopterous parasites. Of parasitic 

 Diptera several have been noticed ; one, a large hairy fly ( Masicera 

 myoidaa / ), is a rapacious enemy. In another case it appears the infestor 

 may be simply a scavenger, as its larva had only been noticed about a 

 decomposing caterpillar that had succumbed apparently from some 

 previous trouble. Its pupa winters over as do the numerous puparia of 

 another species whose presence within the galls was not understood. But 

 they occur so commonly and in such numbers as to be reckoned with, in 

 the life that flourishes here. Of the visitors, transient and permanent, 

 which make these burrows their domicile, to the discomfiture of the original 

 tenant, the most numerous and obtrusive are those common myriapods, 

 the "sow-bugs," which gain access in some numbers through the ventilator, 

 and later, by the exit door crowd the chamber to its full capacity. From 

 twenty to thirty are often packed about the chrysalis, which wriggles and 

 spins around as their movements excite it. We might fancy maritima 

 pupae have acquired their unusual activity and freedom of movement from 

 the turmoil going on about them. It is due to these visitors that the 

 hinged lid of the exit door is so soon broken down, and then such an 

 enticing aperature naturally suggests security to other denizens of dark, 

 damp places. Centipedes, snails, slugs, stray Coleoptera, and many 

 species of ants are regularly seen. While these are mere visitors that 

 congregate after the pupal change, and do not molest the pupa, unless it 

 has died from fungous disease, the actions of two of the ants always appeared 

 suspicious. In any breeding experiments with this genus the first move is 

 to guard against the attacks of two common house-ants, these minute 



