880 General Notes. | September, 
ON THE ANTHRACARID&, A FAMILY OF CARBONIFEROUS MACRU- 
ROUS DECAPOD CRUSTACEA, ALLIED TO THE Eryonip&.'—Havin 
been kindly favored by Messrs. R. D. Lacoe and J. C. Carr with 
the opportunity of examining their collections of nodules from 
Mazon creek, containing Anthrapalemon gracilis Meek and 
Worthen, I have been able to discover some features probably 
not shown in the specimens examined by those paleontologists. 
The newly observed characters are the carapace with its rostrum, 
showing that the American species in these respects closely 
resembles the European ones figured by Salter, the founder of 
the genus. Moreover, specimens show the entire thoracic legs, 
while the antennz of both pairs were almost entirely shown. 
The fact that the first pair of thoracic feet were scarcely larger 
than the succeeding pairs shows that Anthrapalemon cannot be 
placed in the Eryonidz, but should form the type of a distinct 
group of family rank, none of the existing Macrura having such 
small anterior legs. At the same time the Carboniferous Anthra- 
caridz were probably the forerunners or ancestors of the Meso- 
zoic and later Eryonidz 
e genus Anthrapalemon, a Carboniferous fossil, was first 
described by J. W. Salter in the Quarterly Journal of the Geo- 
logical Society of London, (XVII, 529, 1861). The name given 
to the fossils has, the author remarks, “only a general significa- 
tion, and is not intended to indicate.a a relation to Palæmon. 
Minster, &. * * * It is broader than the general form of 
the Astacidz, or than Glyph and its Liassic allies, but much 
narrower than Eryon.” Salter’s type species is Anthrapalemon 
grossarti Salter. With this species the American A. gracilis is 
congeneric. A closely allied English form of A. dubius Prest- 
wich, is referred by Mr. Salter to the subgenus Palæocarabus, a 
name less fitting than Anthrapalemon. The telson, unlike that 
of any other macruran, fossil or recent, so far as I am aware, is 
differentiated into three portions: the basal, central piece is some- 
what polygonal, a little longer than broad; it is separated by a 
inct suture from a small triangular terminal piece which forms 
the apex of the telson. Between the outer half of the entire telson 
is a large broad lobe which is fringed with sete. At rst I 
ed it as a subdivision of the inner lobe of the last uropoda 
_ or abdominal feet, but no instance among the Decapoda is known 
to us in which thedast pair of uropoda have more than two lobes 
or divisions, and I have therefore been inclined to associate the 
_ innermost of the three setiferous lobes with the telson, and to 
 regar | the telson «co mig into two median and two lateral lobu- 
: Whether the two lobes belong with esa 
ea or eas pye will leave for the present an open quest 
Read before the National Academy of Sciences, April, 1885. 
