14 LYCiENA ir., III. 



with dissections. I liacl asked Dr. Hunt -whether there were special glands be- 

 neath the membrane of 11, and an opening at the top of the Ye.sicle. Neither 

 gland nor orifice was discovered. The tluid appeared to exude through minute 

 pores all over the membrane. Nor was there any connection between the tubes 

 of 12 and this organ of 11.* 



Dr. Aug. Weismann wrote : " You should try and observe what enemies the 

 larvte have. It is conceivable that there are such enemies as are afraid of ants." 

 I have found three species of parasites about these larva?. One is dipterous, a Ta- 

 china fly. This deposits eggs on the skin of the larva in second larval stage, and 

 on the second or third segment. As the grubs hatch, they eat their way through 

 the skin, and emerge when full grown in the last larval stage, and make for them- 

 selves a hard pupa case, out of which in a few days comes a fly. Two others 

 arc hymenoptcrous and minute. One is identified by Prof. Riley as Apantdes 

 congregahis Say. The eggs of these species are deposited singly within the very 

 young larvae, and the grub eats its way out when the larva is but half grown, and 

 proceeds to spin for itself a cylindrical cocoon of yellow silk, from which in a few 

 days the perfect insect will break forth. The fourth parasite is also hymenopte- 

 rous, an Ichneumon fly, a species of Anomalon, as Mr. E. T. Cresson tells me. 

 This appears to sting the larva only in the last or perhaps the last two stages. 

 The destruction of larva? by these and other parasites is immense. If any of 

 them attack the mature larva, as the Anomalon does, the grub will pass into 

 the chrysalis and destroy that, and multitudes of chrysalids of different species of 

 butterfly do so perish. But our Lyciena appears to be singularly free from para- 

 sites in the pupa stage, and indeed I have never lost one from such cause. Why 

 it is so favored will perhaps appear from the incident I relate. On 20th June, 

 1878, in the woods, I saw a mature larva on Rattle-weed, and on its. back, facing 

 to the tail, stood a large ant. At less than two inches behind, on the stem, was 

 one of these Anomalon flies, watching its chance to thrust its ovipositor into the 

 larva. I bent the stem and held it horizontally before me without alarming 

 either of the parties. The fly crawled a little nearer and rested, and again 

 nearer, the ant standing motionless, but plainly alert and knowing of the dan- 

 ger. After several advances, the fly turned its abdomen 

 under and forward, thrust out the ovipositor, and strained 



* The figure I- on Plate is too small to show distinctly the position of the 

 organs on 11 and 12, and Mrs. Peart has therefore made a greatly enlarged 

 fi'j:nre of the last segments of P.^ctidarfjiohs larva to accompany ihis note : 

 a indicates the opening on 11 with its raised lips; h, the position of the tnbcs 

 on 12, wholly withdrawn; c, the top of the tube as it appears when slightly 

 protruded ; d, still farther projected, the tentacles in pencil. The little rings, 

 without letter, indicate the spiracles, or breathing holes. 



