HAHDWICKE'S S CIEN CE-GOSSIF. 



93 



horny skeletons of Gorgonia flabellum on the beach 

 near Boscastle; and happening to visit Tintagel 

 after a heavy ground sea I found the shore literally 

 strewed with them, in all states of preservation. In 

 a few cases there were fragments of the coenosarc 

 still clinging to the sclerobasis, but I was not for- 

 tunate enough to find a living specimen. This fact 

 would seem to point to the conclusion that they had 

 been carried a considerable distance, and had 

 suffered much buffeting in their passage. I may 

 add that the local Cornish name is Sea-thorn. — 

 W. A. G., Richmond. 



Popular Errors. — It may interest " C. K. R." 

 to know that in some parts of Kent there is an idea 

 prevalent that upon the belly of the " deaf adder " 

 may be traced the words : — 



" If I could hear as well as I can see, 

 Neither man nor beast should pass by me." 



The notion that the adder is deaf is by no means a 

 modern one. We find it referred to inPsalm lviii. 4 : 

 " Like the deaf adder that stoppeth her ears." — 

 E. T. Cox. 



Eggs or Lepidoptera. — " G. H. B." will find a 

 good deal of information on the subject of pro- 

 curing and preserving these eggs in Dr. Knaggs's 

 " Lepidopterist's Guide." I have procured several 

 by breeding the females, many of which will lay 

 freely in captivity. I do not know of any method 

 of preparation by means of which the natural form 

 and delicacy of the eggs can be rendered perma- 

 ment, but recommend their examination while fresh. 

 — R. Egerton. 



Opercula. — I have some opercula similar to 

 those described by "J. W. K." (p. 69). They be- 

 long to the genus Turbo; but as I have not the 

 shells, I have been unable to ascertain the species. 

 — R. Egerton, 31, Victoria Road, Kensington. 



Gizzard op Flea. — Among the interesting ob- 

 jects for the microscope for which we are indebted 

 to the dexterity and the patience of the preparers, 

 there is one of great beauty known as the " Gizzard 

 of a Flea." Now as Monsieur Dujardin, in his 

 work on the microscope, which, though of an old 

 date, remains as yet unsurpassed by any modern 

 book for the accuracy of its details, makes no men- 

 tion of the flea's gizzard, I beg to invite one or 

 more of your numerous readers to enrich the pages 

 of Science-Gossip with a few particulars regarding 

 the construction and use of the remarkable organ 

 in question.— C. G. Martens. 



Fossils of the Dolomitic Conglomerate. — 

 Can'lyou, or any of your readers, inform me whether 

 any fossil mollusca have ever been found in the 

 Dolomitic conglomerate? I can find no mention of 

 such ; hence I was both surprised and gratified at 

 finding the other day,in that formation, near Frome, 

 Somerset, ten species of mollusca, besides a small 

 striated fish-tooth of the former; seven were Lamelli- 

 branchiata, including members of the genera Ostrea, 

 Avicula, Lima, Pecten, and Modiola. There were 

 also a small Gasteropod, and two Brachiopods— a 

 Bhynconella, and a remarkable shell (Discina?) 

 with a limpet-shaped upper valve, and a concave 

 under valve with a deep recess towards the pos- 

 terior part. The fossils altogether, though differing 

 specifically from any others that I am acquainted 

 with, are decidedly, I should say, of Mesozoic rather 



than of Palaeozoic character. This would tend to 

 confirm the present opinion with regard to the posi- 

 tion of the Dolomitic conglomerate — viz., Triassic 

 rather than Permian. It has been suggested that 

 this formation is the representative in England of 

 the missing Muschelkalk of Germany. The con- 

 glomerate is shown in the section near Frome, with 

 diagrammatic distinctness resting unconformably 

 upon the mountain limestone, while above it is 

 overlaid conformably by the inferior oolite. Its 

 thickness here varies from two to seven feet, and it 

 consists of pebbles of the subjacent mountain lime- 

 stone rounded by attrition, and cemented together 

 by a light grey matrix of magnesian limestone, 

 which by exposure becomes decomposed into a 

 soft greenish-grey earthy matter. It is in two 

 or three beds, each from one to two feet in thick- 

 ness, parted by a thin stratum of black clay. — 

 H. F. Parson. 



A Turbid Aquarium (see Feb. No., p. 46). — 

 Occasional opacity in an aquarium is, in many in- 

 stances, caused by changes of temperature. Fine 

 particles are separated from the water as the tem- 

 perature falls, which, when it becomes water again, 

 dissolve and disappear. But can the observer be 

 absolutely certain that some portions of the mud 

 are not agitated, and thus mixed with the water, 

 through the agency of some of the creatures in the 

 aquarium — if not by the fishes, possibly by the 

 beetles ? If he has there any beetles of size, it is 

 possible they have caused the turbidity : those be- 

 longing to the genus Dytiscus I have repeatedly 

 noticed have a great liking for a mud-bath. The 

 presence of some moderate-sized pieces of charcoal 

 would, it is likely, be of service where mud or soil 

 forms part of the substratum. Sometimes, it is true, 

 an aquarium will thrive for a good while with such 

 substances contained in it; but the most successful 

 experiments have been made with aquaria having 

 only shingle or pebbles at the bottom. There are 

 very few plants worth growing which actually re- 

 quire the nutriment described ; those mentioned 

 usually thrive on water only. — W. R. H. 



Camphor v. Benzole. — How are we to preserve 

 our insects ? Hard work enough is it to secure 

 them sometimes, and when we have them snug in 

 our cabinets we naturally wish to preserve them 

 from all parasites, and also to keep them in good 

 condition. Mr. Newman and others condemn the 

 use of camphor as inoperative in the case of certain 

 enemies, and also as a cause of the appearance of 

 greasiness in a cabinet. One is desirous of believing 

 aught that comes from the lips or pens of those 

 whose 



" Long experience doth attain 

 To something like prophetic strain." 



Yet, when we consider for how very many years 

 camphor has been used as a preservative in cabinets 

 and cases, it is not easy to convince ourselves that 

 it is useless and even injurious. On one point, cer- 

 tainly, I am disposed to make a stand. The chemi- 

 cal composition of camphor is well known, and, if 

 the drug be pure, as it generally is, not being 

 notably adulterated, there is nothing in it to deposit 

 grease on insects, paper, or wood. Its volatility is 

 such, as all have noticed, that, when enclosed, it 

 vaporizes away until none is left. Unless, then, it 

 can be shown that the fumes of the camphor, im- 

 pregnating the insects, do, by some decomposition 

 they occasion, cause grease to be deposited, I can- 

 not see how the camphor can be held guilty ; and 



