Aug. 6, 1874J 



NA TURE 



277 



SOCIETIES AND ACADEMIES 



London 



Royal Horticultural Society, July 15. — Scientific Com- 

 mittee. — A. Smee, F.R.S., in the chair. — Mr. McLachlan 

 showed damson leaves affected with a gall produced by Voknlifcx 

 pruni, a species commonly found on the sloe. — Dr. Hooker sent 

 a note statint; that since the last meeting a Ward's case had been 

 received from Mr. Moseley of the Chalhiigcr, and though all the 

 plants were dead, the soil, when spread out and watered, yielded 

 numerous seedlings of Pringlca and Azcrdla. — Dr. Masters ex- 

 hibited a branch of Privet, furnished with large wroody spines. 



General Meeting. — Dr. Masters, F. R.S., in the chair. — The 

 Rev. M. 1- Berkeley commented on the most important of the 

 objects submitted to the Fruit and Moral Committees. 



PHILADEt.riIIA 



Academy of Natural Sciences, Dec. 30, 1S73. — Dr. 

 Ruschenberger, president, in the chair. — The following paper 

 was presented for publication : — Remarkable variations in 

 coloration, ornamentation, &c., of certain larv.i; of Noc- 

 turnal Lepidoptera, by Thos. G. Gentry. — On report of 

 the committees, the following papers were ordered to be printed : 

 Description of seven new species of Uiiioiiidi? of the United 

 States, by Isaac Lea ; Description of three new species of 

 UnioiHS of the United States, by Isaac Lea. 



Jan. 6. — Dr. Ruschenberger, president, in the chair. — 

 Dr. J. G. Hunt remarked that the structure of the Schhita 

 ptisilla differed widely from that of our other indigenous 

 schizaceous ferns, viz , Lv^oiiinm palmatum, and its morpho- 

 logical elements are unlike tliose of our ferns in general. 

 The barren frond of Schhica fiisiUa is marked on its epi- 

 dermal surface with a lioiiMe line of stomata, and these organs 

 e.Ktend the entire length of the frond. The cells which make up 

 the interior of this delic.ite fern are cylindrical and vary in size, 

 but their distinctive characters lie in minute projections or out- 

 growths from all sides of the cells, and these projections meet 

 and are articulated with corresponding outgrowth from adjoining 

 cells, so that the cells of Scliizita have penetrating between them 

 in every direction intercellular spaces and channels of rcmaikable 

 regularitv and beauty, and so characteristic is this plan of cell- 

 union that the botanist need find no difficulty in identifying the 

 smallest fragment of the plant. I'his morphological peculiarity 

 has not been noticed before. — Mr. Thomas Meehan exhibited 

 some flowers of Passifloi-a quadraii^ularis, in which some of 

 them had the pistils almost wanting, while the flowers were perfect 

 in all other particulars. He said it was well known that in culti- 

 vation this plant never produced fruit unless by artificial cross- 

 impregnation, but he thought the tendency to abort in the female 

 flowers, and thus approach the classes which were in structure as 

 well as practically uni-sexual, had not been noticed before. 

 There was a species in New Zealand, however, known to be 

 moncecious, and it might be just possilile that the Passifloraccr, 

 with mostly hermaplirodite (lowers, were following in the wake 

 of the allied CKcurbitacnc, in which a complete separation of the 

 sexes was the rule. 



Jan. 13. — Dr. Ruschenberger, president, in the chair. — Prof. 

 Leidy remarked that two species of Ilydia were common in the 

 neighbourhood of Philadelphia. One is of a light brownish hue 

 and is found on the under side of stones and on aquatic plants 

 in the Delaware and Schuylkill rivers, and in ditches communi- 

 cating with the same. Preserved in an aquarium, after some 

 days the animals will often elongate the tentacula for several 

 inches in length. The green flydra is found in ponds and 

 springs attached to aquatic plants. It has from six to eight 

 tentacles, which never elongate to the extent they do in the brown 

 Hydra. In winter the animal is frequently observed with the 

 male organs developed just below the head as a mamma-like 

 process on each side of the body. He had not been able to 

 satisfy himself that these Ilydnc were different from //. fusca 

 and //. viridis of Europe. Prof Agassiz had indicated similar 

 coloured forms in Massachusetts and Connecticut, under the 

 names of //. carma and //. i^raalis. Of the former he remarks 

 that it has very short tentacles, and, if this is correct under all 

 circumstances, it must be ditTerent Irom our brown Hydm, which 

 can elongate its arms for 3 in. or more. 



Jan. 20. — Dr. Ruschenberger, president, in the chair. — Prof. 

 E. D. Cope described some species of extinct tortoises from cer- 

 tain formations of north-eastern Colorado, which had been pre- 

 viously found in the Fort Union or lignite beds of the Missouri 



river region by Dr. Hayden. He had in 186S recognised the 

 age of the latter as Creiaceous, contrary to the opinion expressed 

 by some geologists, that the formation both in Dakota and 

 Colorado is Tertiary. — Mr. Co]ie incidentally mentioned the 

 recent discovery of remains of Dinosaurs in the lignite beds of 

 Colorado, which were thus proved to belong to the Cretaceous 

 period, and not Tertiary, as the evidence of the fossil plants had 

 been interpreted by Mr. Lesquereux and others. Dr. LeConte 

 expressed his great satisfaction at the complete confirmation, by 

 his friend Mr. Cope, of the statements he made several years 

 ago (Notes on the Geology of the Survey for the Extension of the 

 Union Pacific Railway, Eastern Division : Philadelphia, Feb. 

 1S67), concerning the Cretaceous age of the lignites at the eastern 

 base of the Rocky Mountains, from near Denver southwards into 

 New Mexico. 



Jan. 27. — Dr. Ruschenberger, president, in the chair. — Prof. 

 Cope made some observations on the age of the lignite and other 

 corresponding formations of the West, and especially its supposed 

 equivalent in Northern Colorado. He referred to his determina- 

 tion of the Upper Missouri formation as Cretaceous in 1868 ; of 

 the Wyoming Bitter Creek series as of the same age in 1872. 

 He now added the Colorado strata to the same, on the evidence 

 of vertebrate remains procured by himself during the past season, 

 in connection with the United States Geological Sui"vey under 

 Dr. F. V. Hayden. These remains consisted of Diiwsauria of 

 three species, tortoises of five, and a single species of crocodile. 

 Five of the genera were diagnostic. The Dinosauria were re- 

 ferred to the old genus Hadrosaiints and the new genera Polyojtax 

 and Cionodon. The Cionodon arctatus was a large herbivorous 

 saurian, allied to Hadrosaiinis, but with a most complex and 

 singular type of dentition ; the size that of a horse. The other 

 two species are much larger. 



Boston, U.S. 



Society of Natural History, Feb. 18. — Dr. H. Hagen 

 read a paper On amber in North America, calling alt:n- 

 tion to a forgotten paper by Dr. G. Troost, published in 

 SiUiman's American J oiirnal of Siiencc, 1821, entitled, ''De- 

 scription of a variety of Amber, and of a fossil substance 

 supposed to be the nest of an insect, discovered at Cape 

 Sable, Md." This piper contains much more than its title 

 would indicate, giving an elaborate account of the geologi- 

 cal formation of Cape Sable Dr. Hagen then described the 

 different strata at Cape Sable, as given by Dr. Troost ; compar- 

 ing which with the profile of the coast of SamUnd in Eastern 

 Prussia, where most of the amber was found, he showed there 

 was little resemblance between the two, except the ojcurrence of 

 amber in sandy strata and the agglutination of sand by iron 

 oxide, although whether this sand has any similarity to the glau- 

 conite of the amber strata in Prussia he did not know. A 

 striking difference between the amber strata in Eastern Prussia 

 and in Maryland is the occurrence of lignite only below these 

 strata in the latter and only above in the former locality. This 

 fact perhaps indicates some similarity with the occurrence of 

 amber in the so-called .t/;7/ci/.vi7«i/ of the lignite layers of Prussia. 

 — Dr. Hunt then read a paper on the deposition of clays. Having 

 examined the water of the Mississippi near its mouth, he found 

 it to contain about 1-2000 of stispended matter, chiefly 

 clay, which required from ten to fourteen days to subside. 

 He, however, observed that the addition of sea-water or 

 of salt, sulphate of magnesia, alum, or sulphuric acid, renderel 

 the turbid water clear in from twelve to eighteen hours. He 

 thus explained the ready precipitation of the suspended clay 

 when the river water conies in contact with the salt waters of the 

 Gulf of Mexico, causing thus great deposits of fine mud and 

 helping us to understand the origin of the accumulations of argil- 

 lites and clay slates which are met with in various geological for- 

 mations. An explanation of this phenomenon is to be found, 

 Dr. Hunt thinks, in the researches of Guthrie on the formation 

 of drops (Proc. Royal Soc, xiv., 1S64). Studying the size of 

 drops of water falling fiom a small sphere of ivory, he found 

 that the cohesion of the water was diminished when it held saline 

 matter in solution, as was shown by the smaller size of the drops. 

 This was verified by experiments with solutions of var ous 

 strengths, of nitre and chloride of calcium. It was found liiat 

 the .addition of eight parts of the latier salt to 1,000 parts 

 of water reduced by one-ninth the size of the drops, which was 

 determined by their diminished weight. These results show a 

 diminished cohesion of the liquid to the ivory sphere, from 

 which it was by the force of gravity made to fall. The cohesion 

 in virtue of which extremely attenuated particles of clay are held 



