724 



SCIENCE 



[N. S. Vol. XXX. No. 777 



ical factors at present operative, is not easily 

 established, but observation points strongly 

 toward the latter as controlling forces. 



J. C. Bldmer 



Tucson, Arizona 



DIKES IN THE HAMILTON SHALE NEAR CLINTON- 

 VILLE, ONONDAGA COUNTY, NEW YORK 



The presence of a few igneous intrusions 

 in the almost undisturbed Paleozoic strata of 

 central New York has long been known to 

 geologists. Their extreme rarity, however, has 

 always invested them with a peculiar interest. 



Excluding the Manheim Dike near Little 

 Falls, which lies about seventy-five miles east 

 of Syracuse and which cuts Ordovician strata, 

 we find that these igneous rocks may be 

 grouped geographically into (1) those occur- 

 ring in the vicinity of Ithaca and Ludlowville 

 and (2) those occurring in the vicinity of 

 Syracuse. In both regions the intrusions are 

 peridotite and are mostly true dikes cutting 

 in the first case such Upper Devonian forma- 

 tions as the Genesee shale and the Portage 

 and Ithaca shales and sandstones, and in the 

 second case cutting the Salina beds of Silurian 

 age. 



As far as the writer has been able to learn, 

 the geologically intermediate Hamilton shale 

 has, until now, yielded no dikes and the recent 

 discovery of two in this formation at a locality 

 about twelve miles southwest of Syracuse and 

 about forty miles northeasterly from Ithaca 

 is believed to be a matter of interest. 



The dikes in question are exposed on the 

 south wall of the Clintonville Ravine at a 

 point approximately fifty feet above the level 

 of the Marietta road. The more western is a 

 fine-grained porphyritic rock resembling peri- 

 dotite. What appear to be serpentine grains, 

 produced by the alteration of olivine, protrude 

 from the weathered surface and have the ap- 

 pearance of small pebbles. Another conspicu- 

 ous feature is furnished by large scales of a 

 bronzy mica. This dike has a uniform width 

 of from seven to eight inches and is displayed 

 for about twelve feet on the south bank of the 

 ravine. On the north side it is obscured by 

 talus. Its plane is vertical, while its direction 



is north and south, agreeing in this latter 

 respect with the Ithaca dikes. Wherever ex- 

 amined it presents a very uniform texture, is 

 apparently free from fragments of the sedi- 

 mentary rocks through which it passed, and 

 has produced little contact metamorphism. 



The second dike discovered by the writer 

 lies about two feet and four inches to the east 

 of the first and was not observed until the wall 

 at this point had been cleaned. It has a width 

 of about eight inches. Like the first dike, it 

 is vertical and north and south in direction. 

 It differs, however, from the first dike in being 

 much weathered in places and in containing 

 many shale fragments some of which have a 

 long diameter of three inches or more. 



Burnett Smith 



Department of Geology, 

 Sykacitse University 



guinea pig graft-hybrids 

 In May, 1907, I published results demon- 

 strating, (1) that iso-engrafted ovaries in 

 fowls subsequently exhibit a reproductive 

 function; and (2) that such resulting offspring 

 give evidence of a " soma " or " foster mother " 

 influence.' The same year. Professor Wilhelm 

 Magnus, of the University of Christiania, ob- 

 tained similar results on a rabbit.^ 



The purpose of this note is to record results 

 obtained on a guinea pig. November 6, 1908, 

 the ovaries of a young guinea pig were re- 

 moved and in the former site of the right 

 ovary, the left ovary from a sister guinea pig 

 was engrafted. The guinea pig was bred and 

 in the latter part of July or the early part of 

 August, 1909, gave birth to two young.' As all 

 the animals were mongrels it is obvious that 

 no conclusion regarding foster mother influ- 

 ence is possible. 



In Science,* September 3, 1909, Professor 

 Castle reports the birth of two guinea pigs 

 from a spayed white mother carrying en- 



^ Proceedings of the society, American Journal 

 of Physiology, Vol. XIX., pp. xvi-xvii, July, 1907. 



- Norsk magazin for laegevidenslcaben, No. 9, 

 1907. 



^ November 12, the operated animal gave pre- 

 mature birth to two more young. 



*N. S., Vol. XXX., No. 766, pp. 312-313. 



