296 RECORD OF SCIENCE FOR 1887 AND 1888. 



plates) discusses the characters of the species Acantliotelson sfimpsoni, 

 Meek and Wortheii, and A. eveni, M. and W. Some new facts in regard 

 to them have come to light through the study of additional specimens 

 from the collections of R. D. I^acoe and J. C. Carr. The author defines 

 one new species from Mazon Creek, Acantliotelson (?) magister, p. 127, 

 pi. ii, f. 4, 6. In a foot-note (p. 128) some new characters, observed on 

 a larger specimen from Brainwood, Illinois, are made the basis of a 

 brief definition of and the proj^osal of a new generic name, Belotelson 

 (the entire name Belotelson mcujister), for the species. 



In the second paper {2lSb) '' On the Gampsonychida^, an undescribed 

 family of fossil Schizopod Crustacea " (pp. 129-133, pi. iii), the study of 

 specimens of Paloeocaris typus, Meek and Worthen, has induced the 

 author to comjiare them with the genus Gampsoiiyx, " and the result 

 has led to the formation of a family or higher group for the genera, 

 which should probably stand at the base of the Schizopoda, while also 

 serving to bridge over the chasm existing between the Thoracostracous 

 suborders Syncarida and Schizopoda." 



In the third paper (218c) " On the Anthracaridfe, a family of Carbon- 

 iferous Macrurous Decapod Crustacea," pp. 134-139, pi. iv, the author 

 presents new facts regarding the species Anthrapalccmon gracilis, Meek 

 and Worthen, from study of which and comparison with other forms he 

 erects for it and kindred forms the family Anthracaridw. 



A fourth paper {2l8cl) is " On the Carboniferous Xiphosurous fauna 

 of North America," pp. 143-157, pis. v, vi, vii. This paper defines and 

 figures Cyclus Americana Packard, Dipeltis diplodiscus Packard, Prest- 

 loichia dance, Meek, Frestwichia longispina Packard, and Belinurus lacoei 

 Packard. In a note on the validity of the genus Euprobps, the author ex- 

 presses the opinion " tliat the apparent differences between Frestwichia 

 and JEuproops, as stated by Messrs. Meek and Worthen, did not exist 

 in nature." In a footnote, p. 150, the author discusses the characters 

 of Frestwichia, eriensis Williams, and presents reasons for the opinion 

 that the species is not a Frestwichia^ and for it he proposes the name 

 and briefly defines the new genus FrotoUmulus. A synopsis of North 

 American Xiphosura is given, p. 150 ; the name Synziphosura is pro- 

 posed for the suborder, including Bunodidw Packard, Hemiaspida; Zittel 

 (restricted), Fseudoniscidw Packard, and NeoUmulidxe Packard. 



The term Podostoma is proposed on page 150 for the class which in- 

 cludes the two orders (i) Merostomata, with the suborders Xiphosura, 

 Synziphosura, and Eurypterida, and (ii) Trilohita. 



The two articles recorded under the same author's name (218e, 220) 

 are reviews of the monograi)hs above discussed. The first one (218e) 

 is an abstract prepared by the author on the class Podostomata, and 

 contains the substance of the latter part of the fourth paper above re- 

 ferred to (218rf). The article (220) on Fossil Arthropods, in the Ameri- 

 can Naturalist, is a brief notice by the editor of the four papers just 

 mentioned. 



