A. 



Palpi long. Inferior wings when at rest projecting beyond the 

 costa of the superior. Larvae not cylindric, having fascicles 

 of hair down the sides and a dorsal tubercle near the apex. 

 Cocoons long, attenuated, silky and soft. 



a. Antennas curved. Tongue short. Wings denticulated. 



Gastropacha. 



b. Antennae straight. Tongue none. Wings not denti- 



culated. 



Odonestis, 



B. 



Palpi minute. Inferior wings not projecting when at rest. 

 Larvae cylindric clothed with hairs. Cocoons oblong, obtuse, 

 dense and rigid in texture. 



Lasiocampa. 



1. Quercus Linn. — Doji. Brit. Ins. 3. 103 & 104. — Spartii 



Hub. — Esp. 3. tab. 13. f. 2 & 3. a variety of L. Quercus. 



2. Medicaginis. 



3. Trifolii Fab. — Linn. Trans, v. 3. pi. 4;./. 1. — Sepp, v. 2. 



tab. 13 & 14. 



4. Rubi Li?in. — Don. 2. 69.~Sepp, v. 2. tab. 7, 8, & 9. 



The characters that distinguish L. Medicaginis from L. 

 Trifolii are the abbreviated fascia next the base of the supe- 

 rior and the obscure one across the inferior wings : the 

 breadth of that which is parallel to the posterior margin of 

 the upper wings is also greater. Were it not for Esper's 

 figure of the caterpillar (from which ours is copied, and 

 which is referred to by Ochsenheimer) being very different 

 from those of L. Trifolii, so beautifully represented by Sepp, 

 we should have considered L. Medicaginis as a variety only 

 of that insect. Five caterpillars were found near Lyndhurst 

 the end of June, by Mr, Joseph Standish, who fed them upon 

 heath, grass, and medick until the beginning of July, when 

 they were full grown and changed to pupae, from whence they 

 emerged the beginning of the following August. 



The reader is referred to Mr. Haworth's Lepidoptera Bri- 

 tannica (p. 82) for an amusing account of the assembling of 

 males by a virgin female, and to the Introduction to Entomo- 

 logy (vol. i. p. 131), for observations upon a singular property 

 which the larvae of this genus possess, the hair creating ex- 

 cessive irritation and pain when applied to the skin. 



The larvae will probably feed upon most of the Trefoils and 

 Medicks, as the plant figured, Trifolium pratejise (the Common 

 Purple Trefoil), is said to be its food, as well as Medicago lupu- 

 lina (pi. 6), from which our insect has received its name. 



