176

r January,

DESCRIPTION OF THE LARVA OF APAMEA FIS EOS A.

BY WILLIAM BUCKLER.

After fruitless researches at various times during a quarter of acentury by many skilful collectors, desirous to find the larva of thisspecies,—reputed to be abundant in fens and similar places—my hopeof obtaining it had almost died out, but revived towards the end oflast year with encouragement from Mr. W. H. B. Fletcher, when hemade known to me that very strenuous efforts had been devoted to it,and would be continued until the mystery of its habitat was cleared up.

The success that crowns perseverance has in this case beenhappily exemplified by Mr. Albert Houghton, of Wicken, who deservesgreat credit for his praiseworthy efforts in bringing this larva tolight, after it had so completely baffled all who had before searchedfor it in this country. ^

Without calling in question the accuracy or-, Treitschke , whoassigned to fibrosa the flower stems of Iris pseudacorus, I yet mayventure to say there seems to me but little doubt that this conclusionmay have been drawn probably from an aberrant example, as latterlyin England there had come to be a consensus of opinion that it couldnot be found in those stems.

But, however that may have been, it is now certain that I hadthe great pleasure to receive this larva from Mr. Fletcher on the 1stof July, 1883, being one of several Mr. Houghton had a day ortwo before sent to him, and these were supplemented with furtherexamples, and on the 21st, Mr. Fletcher most kindly presented mewith one of the pupse which had resulted from them.

Of course, I tended the larva most assiduously with fresh, butsubstitute food, from the most likely aquatic plants I could find,including at first Sparganium, Iris, and Oarex, giving it the lowerparts of each next the root; but it persistently refused the first twonamed, and ate only of Oarex paludosa, and very sparingly of that asthough not quite to its taste; yet seeing it eat, I was hopeful the firstthree or four days of rearing it, but was soon undeceived, as just withina week it died of atrophy, after vainly wandering about in quest of itsproper food plant, the great fen sedge, Cladium mariscus,

Mr. Houghton was led to bis discovery of the larva by observingthat when the crop of this sedge had been cut and removed there weresome of these plants that had not pushed out fresh shoots, and lookedas though dead in the middle ; these on being closely examined proved