N. A. INVERTEBRATE PALAEONTOLOGY. 729 



spect to the trausitioD. of so-called species from one of the stages to 

 another, but emphatically agrees with Heilprin as to the impossibility 

 of subverting the accumulative stratigraphic evidence, to the effect that 

 the relative superposition of the several principal stages — the Buhr- 

 stone, Claiborne, Jackson, and Vicksburg groups — cannot be otherwise 

 than as heretofore ascertained in hundreds of localities by others as 

 well as by himself 



HiLGARD, E. W.— The Old Tertiary of the Southwest. Amcr. Jour. ScL, 

 3d ser., vol. xxx, pp. 266-269. October, 1885. New Haven. 

 Criticises Dr. Otto Meyer's views as expressed in the June and July 

 numbers of this journal. Does not attach much importance to Plagi- 

 ofitoma dumosum as a significant fossil. Considers Area 3rLssissippiensis 

 as the most characteristic Vicksburg fossil. For the Jackson age the 

 most constant fossil is the Zeuglodon and also Vcnericardia planicosta, 

 which has nowhere been found associated with the characteristic Vicks- 

 burg fauna. Through this widely diffused and universally recognized 

 shell, as well as through the almost equally constant Gastridium vetus- 

 tum and Calyptrophorus veJatus as common fossils, the Jackson fauna 

 connects strikingly with the Claiborne and Buhrstone beds, and the 

 author has found this Venericardia in the latter in almost immediate 

 contact with the Upper Cretaceous rocks of North Mississippi. Upon 

 Dr. Meyer's assumption, the Vicksburg beds, void of both of the above 

 types, would actually be intercalated between this oldest post-Creta- 

 ceous fiiuna and the Claiborne and Jackson beds. However, his as- 

 sumption is abundantly and conclusively disproved by the most direct 

 stratigraphical evidence. 



HiNDE, G. J. — Description of a New Species of Crinoids with Articulating 

 Spines. Annals and Magazine of Natural History, 5tli ser., vol. xv, 

 pp. 157-173, pi. vi, and tig. j). 163. March, 1885. London. 

 Describes the new genus Hystricrinus=:^Arthroacantha, Williams, in- 

 valid, and the new species Hystricrinus Carpenteri from the Middle De- 

 vonian at Arkona, Ontario, Canada. The peculiarity of the species 

 consists in movable spines. 



HiNDE, G. J. — Notice of Hystricrinus Carpenteri, a Crinoid with Artic- 

 ulating Spines. Amer. Nat, vol. xix, p. 706. July, 1885. Pliiladel- 

 l)hia. 



This specimen, from calcareous shales of the Middle Devonian at Ar- 

 kona, Ontario, was described by Mr. G. J. Hinde in tlie Ann. and Mag. 

 Nat. Hist., March, 1885. The genus is identical with Arthrocanthus 

 (Williams), a name preoccupied among the Rotatoria. 



Hyatt, Alpheus. — Structure of the Siphon in the Endoceratidaj. 

 Proc. A. A. A. S., vol. xxxni, i)art ii, pp. 400,491. 1885. Salem. 

 Abstract. Describes the stincture of the siphon of Endoceras and 



