Sepiembek 20, 1895.] 



SCLENGE. 



383 



Western bii-ds are largely at second hand and 

 not very complete, while those of the species 

 with which Mr. Nehrling is personally familiar 

 — comprising the great majority — are full and 

 show a real knowledge of the birds' haunts and 

 habits. Mr. Nehrling is a botanist as well as an 

 ornithologist, and many of his biographies tell 

 more of the flowers and shrubs among which 

 the birds live than of the birds themselves. 



It is gratifying to see this meritorious work 

 pressing so rapidly toward completion. 



C. H. M. 



SCIENTIFIC JOURNALS. 



THE AMERICAN GEOLOGIST, SEPTEMBER. 



Edward Hitchcock: By C. H. Hitchcock. 

 President Hitchcock's name is thoroughly iden- 

 tified with the subject of iohnology and the Con- 

 necticut sandstone. To him belongs the honor 

 of having proved the existence of a large fauna 

 of giant bipeds and quadrupeds in the Trias of 

 New England from their footmarks. The 

 sketch of his life is accompanied by a portrait 

 and an extended bibliography. 



A Rational View of the Keeweenawan : By N. 

 H. WiNCHELL. The author continues his dis- 

 cussion of the Keweenawan from last month's 

 number of this journal. His conclusions are 

 briefly as follows : The so-called basal eruptives 

 (gabbros, etc.) of the Keweenawan are pre- 

 Keweenawan, and are separated from the 

 Keweenawan by a long erosion interval. The 

 lowest beds of the Keweenawan are conglomer- 

 ates and sandstones, and not igneous rocks. 

 With these basal elastics are included the 

 Sioux, New Ulm and Baraboo quartzites. (This 

 seems to be the first time that these quartzites 

 have been assigned to the Keweenawan.) There 

 is not sufficient evidence of a long erosion inter- 

 val between the Keweenawan and the Upper 

 Cambrian. The Animikie is Lower Cambrian 

 in age, and the Olenellus horizon is separated 

 from the Paradoxides horizon by the disturb- 

 ance that closed the Animikie. The Keween- 

 awan eruptive age, following the accumulation 

 of the conglomerates and quartzites above men- 

 tioned, separated the Paradoxides horizon from 

 the Dicellocephalus horizon. 



The Mentor Beds : A Central Kansas Terrane of 

 the Comanche Series : By F. W. Ceagik. These 



beds, named from a small station in Saline 

 county, Kansas, are a terrane of variegated 

 earthy textured marine shales, with intercalated 

 beds of brown sandstone, resting in part con- 

 formably upon the Kiowa shales, and in part 

 unconformably upon the Permian. They are 

 succeeded by the sediments of the Dakota. 

 They were formerly considered by all geologists 

 as constituting a part of the Dakota group, but 

 are now known to belong to the upper part of 

 the Comanche series. The Mentor beds are 

 characterized by a fauna -(which is here listed) 

 related to that of the Denison beds, and still 

 more closely to that of the Kiowa shales, with 

 the latter of which its stratigraphic relation is 

 close. 



The Larval Stages of Trilobites : By Charles 

 E. Bbechee. a common early larval form of 

 trilobites is recognized and called the protaspis. 

 It has a dorsal shield, a cephalic portion com- 

 posed of five fused segments indicating as many 

 paired appendages, and a pygidial portion con- 

 sisting of the anal segment with one or more 

 fused segments. The simplest larvse are those 

 of Cambrian genera. In later geologic time the 

 protaspis acquired additional characters by 

 earlier inheritance, as the free-cheeks, the eyes, 

 the eye-line and ornaments of the test. 



On account of the antiquity and generalized 

 nature of the trilobites, their ontogeny is of 

 considerable importance in interpreting crusta- 

 cean phylogeny. The protaspis and crustacean 

 nauplius are shown to be homologous larval 

 forms, and the latter to have potentially five 

 cephalis segments bearing appendages. The 

 nauplius is considered as a modified crustacean 

 larva. The protaspis more nearly represents 

 the primitive ancestral larval form for the class, 

 and approximates the protonauplius. 



Recent Geological Work in South Dakota : By 

 J. E. Todd. Prof. Todd, State Geologist, pre- 

 sents in a brief letter some points of general 

 geological interest ascertained during this sea- 

 son's work in the Black Hills and in the north- 

 western part of the State. 



the astrophysical journal, august. 

 A New Form of Stellar Photometer: Edward C. 

 Pickering. A new photometer has been de- 

 vised with special reference to the comparison 



