August 9, 1907] 



SCIENCE 



177 



red, two-seeded fruit. The only known Amer- 

 ican thorn that fits this description is C. 

 Margaretta Ashe (= G. Brownii Brit.)- This 

 was not known from the coastal plain region, 

 but there is a specimen in the U. S. National 

 Museum from Maryland. Fig. 5 of plate 99 

 is a young shoot of Cratcegus CrusgalU L. 



Plate 100, Fig. 1, was referred by Linnseus 

 to Cratcegus tomentosa. This is the same as 

 Cratcegus uniflora Muench. or C. parvifolia 

 Alton. It is a common coastal-plain species, 

 which both Banister and Clayton must have 

 collected in Virginia. Clayton mentions but 

 one species with leaves hairy on the lower 

 side, and the reference is doubtless to this 

 species. 



That Linnaeus did not know well the thorns 

 he was describing, is partially proved by his 

 referring C. Phcenopyrum, a five-seeded 

 species, to a two-seeded species. Miller's de- 

 scriptions of the Cratcegi raised in England is 

 invaluable to us in tracing out these Linnsean 

 species. As Miller says, Linnseus was doubt- 

 less misled by Kalm. 



Cratcegus viridis L. was collected and prob- 

 ably described by Clayton. About this species 

 there can be no question, for there is a Clayton 

 specimen of C. viridis in the British Museum. 

 A colored plate was made by Ehret for 

 "Plantse Selects" between 1760 and 1762. 

 This may be the first illustration of Crataegus 

 flava Aiton. It certainly belongs to the flavce, 

 and was raised from seed sent from Carolina 

 by Catesby in 1724. Another American thorn, 

 C. punctata, was illustrated by Jacquin in 

 Hort. Vind., 1770. 



Further Remarhs on the Botanical Explora- 

 tion of the Bahamas: Dr. N. L. Britton. 

 Referring to a previous communication 

 made to the club and to others, printed in the 

 Journal of the New York Botanical Garden, 

 Dr. Britton gave an account of the recent ex- 

 peditions of Mr. L. J. IL Brace to Crooked 

 Island, Acklin's Island, Long Cay (Fortune 

 Island), and Andros, and of his own trip in 

 February and March, in company with Dr. C. 

 F. Millspaugh, to Eleuthera, Little San Salva- 

 dor, Cat Island, Conception Island, Watling's 

 Island, and Long Island. During the progress 



of this trip Mrs. Britton explored the northern 

 part of Eleuthera, and did some collecting on 

 New Providence. The greater portion of the 

 archipelago has now been visited through the 

 cooperation of the Field Museum of Natural 

 History with the New York Botanical Garden, 

 but the extreme southeastern islands, inclu- 

 ding Atwood Cay (Samana), Mariguana, and 

 the Caicos Islands are as yet botanically un- 

 known, and the central portion of the large 

 island of Andros is a ten-a incognita. The 

 small islands on the Cay Sal bank also remain 

 unvisited. Dr. Britton exhibited specimens of 

 many of the characteristic species and re- 

 marked on their distribution. 



The club adjourned at five o'clock until 

 October 8, 1907. C. Stuaet Gager, 



Secretary 



NEW YORK ACADEMY OF SCIENCES — SECTION OF 

 GEOLOGY AND MINERALOGY 



At the regular monthly meeting. May 6, 

 1907, the following papers were presented: 

 Correlation of the Newark Trap Rochs of New 



Jersey: Professor J. Volney Lewis. 



The disconnected extrusive traps west of 

 the Watchung Mountains may be explained 

 in several ways, but they are probably the re- 

 sults of scant eruptions, the New Vernon 

 crescent being the upturned western edge of 

 the Long Hill trap. The extrusives at Sand 

 Brook and New Germantown are probably 

 outlying remnants of, or at least contempo- 

 raneous with, the flows of First and Second 

 mountains. 



Darton's dike-and-sheet hypothesis of the 

 Palisades sill is not supported by the facts, the 

 trap being roughly conformable to the strata, 

 so far as known, in all directions. The chance 

 of the fissure of intrusion coinciding with the 

 western flank of the Palisades from Wee- 

 hawken to Haverstraw is exceedingly small. 

 On the other hand, data now available quite 

 satisfactorily establish the connection between 

 the Palisades and the trap of Rocky Hill to 

 the southwest, and a section along the Dela- 

 ware River shows a threefold repetition of 

 this by faulting. Thus there is but one in- 

 trusive sheet, which gives off numerous dikes 



