The habits of the larvae are most remarkable : they cut pieces 

 out of the leaves of the Water-lilies, Frog-bit, Duck-weed and 

 other floating plants, with which they cover themselves as with 

 a shield, rendering themselves so difficult to be seen, that when 

 at rest it is almost impossible to detect them. When they are 

 desirous of removing to any distance, I believe they will leave 

 their cases, (probably during the night, when they are not in 

 danger of being punctured by Ichneumons or flies,) as I have 

 seen them wandering about at that period without their cases. 



I have on a former occasion alluded to the Scopula Snmbu- 

 calis having been included in this genus; but however its ap- 

 pearance may lead any one to suppose it is an Hydrocampa, 

 its structure and oeconomy will at once determine it to belong 

 to another group. For the same reasons H. literalis ought to 

 be removed ; and there will then remain two divisions. 



I regret not being able to transcribe the interesting histories 

 of some of these insects from Reaumur and De Geer, which 

 have been abridged by M. Duponchel in his excellent conti- 

 nuation of Godart's " Lcpidopteres de France" 



A. Labial palpi straight and rather drooping. 



1. H. literalis Hiib. t. 13./*. 86. — reticularis Linn. Cab. — Faun. 



Suec. 1355. — argentalis Fab. — July, moist places. 



B. Labial palpi recurved, short and very scaly. 



2. H. Potamogata L. — Don. 11. 363. 1. — Nymphaealis Hm6., 



from whom the caterpillar in our plate is drawn, to 

 show its curious habitation : it feeds also on the Pota- 

 mogeton natans. — M. July and b. of August, swampy 

 places on heaths, Hants; e. August, males in mea- 

 dows and on Water-lilies, borders of rivers. 



3. H. Nymphaeatai. — Potamogalls ^//i^. — stagnata Z)o;i. 11. 



363. 2. — M. July, moist places round London, &c. — 

 The caterpillar feeds on the Duck-weed. 



C. Labial palpi recurved, slender and sparingly clothed. 



4. H. Lemnata L. — Don. 8. 266. 1 & 2.— uliginata F. ? .— 



M. May, moist places ; e. July, Fulham, on the Htj- 

 drockaris Morsus-rance (PI. 307.) and the Duck-weed. 

 — The caterpillar forms cases like H. Potamogata. 

 ¥'. H. raagnificalis OcJi.—Hiib. tab. 16./. 104. $ .—Stated by 

 Treitschke to be a British insect. 



5. H. Stratiotata Z/. — Curt. B. E. pl.^dB.S ? (drawn rather 



larger than life). — B. July, ponds. — The caterpillar 

 feeds on the Stratiotcs Aloides (PI. 488.) : it is fur- 

 nished on each side with external tubes connected 

 with the tracheae, which look like hairs : vide De Geer, 

 V. l.t. 2>1.f. 2—6. 

 The Plant is Ni/mph£ea{Nuphar Smith) Zm^^a! (Yellow Water- 

 lily). The leaf is reduced about two thirds. 



