438 ZOOLOGY. 



Parasitic Crustaceans. 



The extent to wliicli fishes of various kinds are infested with Crus- 

 tacean parasites is little known. A considerable proportion will yield 

 parasites to the careful searcher. Mr. A. Valle has examined a large 

 number of Adriatic fishes, and found G9 species of entomostracans 

 alone. Out of 670 fishes examined, as many as -250 had entoraos- 

 tracan parasites. A new species of the remarkable genus Philichthys, 

 named P. EicMardi, was discovered in the canal of the preopercular bone 

 of the sparoid fish known as Box salpa. — (Bull. Soc. Adriat. Sc. Nat., vi, 

 pp. 65-81.) 



A fossil Tertiary Cray-fish. 



The fresh-water crayfishes of the family Astacidce and like ani- 

 mals are of new interest since the publication of Professor Huxley's 

 monograph on the craj^-fish, and in view of the peculiarities of their 

 distribution. The representatives of the family inhabiting the waters 

 of the northern hemisphere are divided into genera variously distrib- 

 uted. They resemble each other closely externally, but arc distinguished 

 especially by the number of the gills. The typical species constitute 

 the genus Astacus^ which is developed in the Old World, and also on 

 the Pacific slope of North America, while the species of the eastern 

 waters of North America belong to a pecular genus, named Camharus. 

 These types are of considerable antiquity, and Professor Packard has 

 discovered in the lower Tertiary shales of Western Wyoming, which 

 are supposed to be of the Eocene age, remains which he refers to the 

 limited genus Camharus, with the name Camharus primwvus. The 

 species, in his own words, "is exceedingly interesting, from the fact 

 that it represents a jDeriod in which heretofore no fossil cray-fish has 

 been found. The soft, fine, fossil, clayey shales of the Bear River Ter 

 tiaries contain not only a good many herring-like fish, but also genuine 

 •skates. The presence of land plants, mingled with marine animals, 

 shows that the waters were fresh, but communicated with the sea. The 

 ■conditions were apparently those of a deep estuary into which fresh- 

 water streams ran, and in these rivers lived the cray-fish." 



It is claimed that "the discovery of an apparently fresh-water 

 Camharus in the Green River beds of Northern Wyoming, which are 

 supposed to be lower Eocene strata, fills up a break in the geological 

 series hitherto existing between the Cretaceous and Pliocene cray-fishes, 

 and shows that the dynasty of fresh-water cray-fish, now so powerfully 

 developed in the TJn'ted States, began its reign during the early Ter- 

 tiary period." 



ARACHNIDS. 

 1. FAUN^. 



Ewope. 

 Simoti ■(Eug.)' Les Araclmides de France, t. 5. 1. partie, contenant les famiUes 

 des EpeiridiTB (suppl6ment) et des Tberidionida) (commencemeiit). Paris, Roret, 

 1881. 8vo. (186 pp., 1 pi.) 



