HAllDVVICKE'S SCIENCE -GO SSI P. 



and concretions of serpentine, and is traversed by 

 veins of chrysolite ; the former an original part of 

 the deposit, the latter evidently of subsequent for- 

 mation. A thin section, 54 inches in depth, showed : 

 — 1. Limestone, with crystals of dolomite and frag- 

 ments of Eozoon; 2. Eine-grained limestone, with 

 granules of serpentine, casts of chamberlets of Eo- 

 zooii and of small Eoraminiftra; 3. Limestone with 

 dolomite, and containing a thin layer of serpentine; 

 4. Limestone and dolomite, with grains of serpen- 

 tine and fragments of supplemental skeleton of Eo- 

 zoon; 5. Crystallized dolomite, with a few fragments 

 of Eozoon in the state of calcite ; 0. Limestone con- 

 taining serpentine, as No. 2. The author criticised 

 some of the figures and statements put forward by 

 Messrs. King and Rowney, and noticed two forms 

 of Eozoon, which he proposed to regard as varieties, 

 under the names of minor and acervulina. He stated 

 that fragments of Eozoon, included in dolomitic 

 limestones, have their canals filled with transparent 

 dolomite, and sometimes in part with calcite. In 

 one specimen a portion was entirely replaced by 

 serpentine. The author called particular attention 

 to the occurrence of serpentinous casts of chamber- 

 lets, single or arranged in groups, which resemble 

 in form those of the Globigerine foraminifera. 

 These may belong, either to separate organisms, or 

 to the Acervuline layer of the Eozoon ; the author 

 proposes to call them Archceospherinfe, and de- 

 scribes them as having the form and mode of 

 aggregation of Globigerina, with the proper wall of 

 Eozoon. The author discussed the extant theories 

 as to the nature of Eozoon, and maintained that only 

 that of the infiltration of the cavities of foramini- 

 feral structure with serpentine is admissible. He 

 particularly referred to the resemblance of weathered 

 masses of Eozoon to Stromatoporoid corals. 



Eossil Frogs. — Professor Newberry, director of 

 the geological survey of Ohio, has made additional 

 collections in the coal-measures of new fossils. The 

 vertebrate remains of land animals of carboniferous 

 age have as yet only been found in Ohio, within the 

 limits of the United States. These include thirty- 

 three species of Batrachians, but no reptiles or 

 higher vertebrata. One of the recent novelties is 

 a species of the genus Ceraterpeton, the first time 

 a European genus has been detected in America. 

 It was as large as a rat, and had a pair of stout 

 horns on the back of its head, in the position and 

 having much the form of those of an ox. The skull 

 is sculptured by rows of small pits, separated by 

 fine radiating ridges. 



Tertiary Trigonia. — This peculiar genus of 

 bivalve shells, so abundant in the fossil state in the 

 secondary rocks of Europe, and still abundant in 

 the living state in Australiau seas, has hitherto 

 been remarkable for its apparent absence in the 



tertiary strata— an evident anomaly. Professor 

 M'Coy, however, has just described a third species 

 of Trigonia (having previously described two others 

 from the tertiary formations near Melbourne). It 

 was found associated with characteristic tertiary 

 fossils near the Gippsburgh lakes. He names the 

 species Trigonia Hotcitti. 



NOTES AND QUERIES. 



Contamination of an Aquarium. — I suspect 

 "W. H. C.'s" aquarium (Science-Gossip, p. 47) 

 is infested with a confervoid growth, which, when 

 once introduced, is most difficult to eradicate. The 

 germs usually arrive in some pond-water, or perhaps 

 attached to a plant, aud the increase is rapid, 

 especially in mild weather. As " W. H. C." ob- 

 serves, removal of the living contents of the aquarium 

 does not remedy the evil. You may run off the 

 water, scour the sides and bottom of your aquarium, 

 and wash carefully all objects before replacing them ; 

 but some animal or plant is almost sure to carry an 

 unperceived fragment, which is sure to "increase 

 and multiply." The only plan in such a case is to 

 start de novo. Occasionally turbidity arises from 

 the non-preservation of the equilibrium between 

 the animal and vegetable existences in the aquarium. 

 A slight amount of attention will remedy this. A 

 lump or two of charcoal, judiciously hidden, helps 

 to keep all pure. I have noticed that it is a very 

 common error to crowd too many fish into an 

 aquarium. — /. R. S. C. 



Aphides and Honey-dew. —There has been 

 much discussion as to the nature and the source of 

 this peculiar dulcet compound. The November 

 number of the Entomologist contains an interesting 

 note showing that the recent observations of Dr. 

 Hooker and Mr. Doubleday confirm a statement 

 made by a naturalist a century ago, that there are 

 two kinds of honey-dew, one exuded by the leaves 

 or shoots of plants under certain conditions, and 

 the other produced by aphides. In both, probably, 

 the chemical composition is nearly similar, the 

 aphides passing the sap through their digestive 

 economy without producing much change therein, 

 except it be that the'saccharine matter is increased. 



—j. r. s. a 



Destruction of Ants. — To extirpate colonies 

 of these is not so easy, but their numbers may be 

 considerably reduced by Mr. Newman's plan, which 

 consists in making a strong syrup of coarse sugar, 

 and immersing pieces of string or rope in this. 

 These are laid in the tracks, and when the ants 

 swarm upon them they are taken up and plunged in 

 boiling water. 



Disease in Elm-trees. — There is a public walk 

 on the bank of the river Taw planted on both 

 sides with elm-trees. They were planted in 1812, 

 and are about 30 feet high, and appeared very 

 healthy until the last few years. About six years 

 ago they began to die away, and have continued to 

 do so with such rapidity that at the present time 

 mere than a quarter of them have been destroyed. 

 They are first noticed to die away in the uppermost 

 branches, and the decay gradually finds its way to the 

 trunk. This is accomplished in about eight or nine 

 months. Various suggestions have been made as 



