North American pal^,ontology. ' 267 



Packard, A. S. Geological Extinction and some of its Apparent 

 Causes. (Araer. Nat., vol. xx, pp. 29-40, January, 1886. Philadel- 

 phia.) 



" That there is a limit to the age of species as well as to individuals almost goes 

 without saying. As there is iu each imliviJual a youth, mauliood, and old 

 age, so species and orders rise, culminate, and decline." (This view was 

 first propounded by Prof. Alpheus Hyatt.— Ed.) The causes, however com- 

 plex, are, in the case of plants and animals, apparently physical; they are 

 general and pervasive in their effects, and have been iu operation since life 

 began ; there have been critical periods in paleontological as well as geo- 

 logical history, and periods of rapid and wide-spread extinction as well as 

 continual, progressive dyiug out of isolated species. 



Packard, A. S. Causes of the Extinction of Species. (Pop. Sci. 

 Monthly, vol. xxix, p. 429, July, 1886. ]^ew York.) 

 Abstract of. 



Packard, A. S. Discovery of the Thoracic Feet in a Carboniferous 

 Phyllocaridan. (Read before the American Philosophical Society, 

 February o, 1886.) Proc. Amer. Phil. Soc, Philad., vol. xxiii, pp. 

 380-383, pi. p. 380. 



Describes Cnjptozoe problematicus Packard. 



Packard, A. S. Discovery of Lamellate Thoracic Feet iu the Phyllo- 

 carlda. (Amer. Nat., vol. xx, pp. 155, 156, February, 1886. Phila- 

 delphia. 



Describes the thoraclclimbs and regards the parts preserved as the homolognes 

 of the exopodites of Nebalia. The author named the specimen in MSS. 

 Cryptozoe prohl^maticvs, as he was in doubt as to its affinities. A descrip- 

 tion of the new genus and species will appear hereafter, with figures. 



Packard, A. S. {See Dames.) 



Panton, J. Hayes. Fragmentary Leaves from the Geological Records 

 of the Great Northwest. A paper read before the Society on the 

 evening of 24th January, 1884. (Manitoba Hist, and Sci. Soc, \^ in- 

 nipeg. Transactions, No. 4, season 1883-'84, pp. 1-9, 1884. Winni- 

 peg.) 



Mentions vertebrae, thigh bones, and a hip joint of ''cretaceous dinosaurs" ?. 

 Mentions also the occurrence of various invertebrate Laramie and Cre- 

 taceous fossils. 



Panton, J. Hayes. Gleanings from Outcrops of Silurian Strata in the 

 Red River Valley. A paper read before the Society on the. evening 

 of 27th November, 1884. (Manitoba Hist, and Sci. Soc, Winnipeg. 

 Transactions, No. 15, season 1884-'85, pp. 1-13, 1884. Winnipeg.) 



Gives lists of Silurian fossils occurring iu the vicinity of Winnipeg. 



Panton, J. Hayes. Notes on the Geology of some Islands in Lake 

 Winnipeg. A paper read before the Society on the evening of Thurs- 

 day, 28tli January, 1886. (Manitoba Hist, and Nat. Sci. Soc, Win- 

 nipeg. Transactions, No. 20, season 1880, pp. 1-10, 1886. Winnipeg.) 



Mentions the occurrence of a number of genera of Silurian fossils. 



