XV. The oldest known Insect-larva, Mormolucoides articulatus, from the 



Connecticut River Rocks. 



By Samuel II. Scuddkr. 



Bead February G, 1884. 



J_ ROPESSOR Edward Hitchcock, who published so extensively upon the footprints 

 found in the sandstones of the Connecticut River was the first to make known the 

 presence in the triassic shales at Turner's Falls, Mass., of insect remains. 1 These he 

 first mentioned in his report on fossil footmarks published by the state in 1858, giving 

 illustrations upon one of his plates, which arc too obscure to be of any value. Judging 

 the creature to be a crustacean, he sent specimens to Prof. J. D. Dana of New Haven, 

 who, in a letter published in this volume by Professor Hitchcock, 

 considered it to be " probably a larve of a neuroptcrous insect," and 

 sent to Hitchcock the cut we here reproduce, in which he regards A. as 

 the head, B to C as thoracic, and C to I), abdominal segments. This, 

 reduced, is the figure given in Dana's Manual of Geology. 



Some years after this, the late Dr. J. L. Leconte, having expressed 

 the opinion from an examination of the figures alone, that Professor 

 Dana was correct in his judgment of the neuropterous character of these 

 remains, and having further referred them more definitely to the Ephe- 

 meridae, Dr. Hitchcock, who never lost the opportunity of changing the 

 name of a fossil, if he thought he could thereby indicate more closely 

 its affinities, proposed that the name of Mormolucoides articulatus, he 

 had at first given it, should be altered to Palepliemera mediaeva. The 

 first name, being in no sense misleading, must, of course, be retained, 

 and indeed fortunately, since this is not the end of the opinions 

 which have been held (and may perhaps yet be held) regarding it. 



Having an opportunity some years since, of studying a slab lent me 

 by Prof. O. C. Marsh, containing twenty or thirty individuals, and of 

 comparing them with others in the Museum of the Boston Society of 

 Natural History, I published my views of the structure and relationship 

 of this fossil larva in the Geological Magazine of London, in which I 

 came to the conclusion that they were coleopterous larvae, and sug- 

 gested that they "remind one of some Cebrionidae," but tin; only larva of thai group 

 whose history is known "lives on the roots of plants and would not be likely to occur in 



S, flg., n. 7, figs. 3-t.— Dana, Ibid.— Scuddkr, Proc. 



Fig. 1, Mormolu- 

 coides articulatus 

 Hitchcock. 



1 Mormolucoidi s articulatus Hitcin ock, [chnol. N. Engl., pp 

 Bost. Soc. Nat. Hist, xi, p, L40; Id., Geol. Mag., v, pp. 218-20. 



Palepliemera mediaeva Hitchcock, Amur. Journ. Sc, [2J xxxiii, p. 452.— Packard, Hull. Essex rn-t 



MEMOIRS 1SOSTON SOC. NAT. HIST. VOL. 111. 



Ill, p. 1. 



