Discovery of Antenncn of Trilobites, — Beecher. 303 
cumulation of snow. The forward movement of the ice-sheet, 
in excess of the amount lost by melting, was just sufficient to 
enable the front to advance slowly: but when it reached the 
boundary of the Driftless Area, a slight change in climate 
overtook it and it began to lose ground, never again to reach 
quite to its old limits. 
ON A SUPPOSED DISCOVERY OF THE ANTENN/E 
OF TRILOBITES BY LINN/EUS IN 1759. 
By C. E. Beecher, New Haven, Conn. 
Previous to the definite discovery of the appendages of tri- 
lobites by Billings 3 in 1870, paleontologic literature contains 
quite a number of claimants to this honor. Most of them, 
however, are manifestly erroneous, and the two or three which 
bear some semblance of validity are too obscure to be of any 
scientific value. Barrande 2 reviews all the reputed discover- 
ies known to him, but curiously enough overlooks what is 
probably the earliest reference to this subject. He concludes 
that — the few scattered observations of parts found which 
might belong to the trilobites have little value and were ac- 
cepted as such b} r naturalists, and also — that these parts of 
the body have never been really observed up to this time by 
any paleontologist. This conclusion has been generally ac- 
cepted, and therefore the subsequent researches of Billings, 3 
Woodward 12 and Walcott 11 have been considered as the pioneer 
discoveries towards an understanding of the ventral structure 
of trilobites. 
In a recent communication to the Geological Magazine 
(March, 1896), Tornquist 9 calls attention to a paper published 
by Linnaeus 7 in 1751), in which a specimen of Entomolithus 
paradoxus Linnaeus (= Parabolina spinulosa Wahlenberg sp. ) 
is described and figured (loc. cit., 1 pi. I, fig. 1), showing ap- 
parently a pair of antenna' in the proper place 
Tornquist believes that this discovery has been lost sight of 
from the beginning, and reasserts the original claim. He gives 
tin- following translation of that portion relating to the 
antenna' (loc cit., p. 22). '"Fig. 1 is one of the clearest 
specimens I ever saw among so many thousands. Most re- 
markable in this specimen are the antenna' in the front, which 
I never saw in any other example, and which clearly prove 
this fossil to belong to the insects' (= Arthropoda ).*' 
