December 30, 19 15] 



NATURE 



501 



ent males and females are about equal in size and 

 number ; but in ripe females spermatozoa can often be 

 seen, and many of the ova are fertilised. Mr. Good- 

 rich brought forward evidence that these spermatozoa 

 are derived from the males, are not developed in the 

 females, and that their presence is due to normal 

 internal cross fertilisation between the sexes. — Miss 

 Marietta Pailis : The structure and history of " Plav," 

 the floating fen of the delta of the Danube. Plav is a 

 Russian word : it signifies the floating thing or float- 

 ing stufi^, and is the name given by the fishermen of 

 the delta of the Danube to a floating raft of vegetation 

 built up almost entirely of living reed, Phragmites 

 communis, Trin., /8. flavcscens, Gren. and Godr., and 

 earth. The variation in length of the aerial portion 

 of the reed-shoots is so striking (they vary from about 

 4 ft. to about 17 ft.), that it suggests the presence of 

 ditferent varieties of reed. Evidence is given that this 

 variation is not specific or due to the factors of the en- 

 vironment, but is inherent in the reed. The different 

 sizes of reed-shoots are held to be different branches of a 

 definite and complicated reed-system, the first and 

 final branches of which do not co-exist. — T. A. Dymes : 

 The seed-mass and dispersal of Helleborus foetidus, 

 Linn. The seeds of H. foetidus, L., are remarkable 

 in being shed from the follicle in a single mass, bound 

 more or less tightly together by a thick, white ventral 

 strip of oleaginous tissue. Owing to the contrast of 

 the shining elaiosome with the almost black seeds, the 

 mass as a whole bears, at a short distance, a deceptive 

 resemblance to the larva of a beetle. Observations 

 were made, over two consecutive nights, on the work 

 of the snails, which disintegrate the mass by devour- 

 ing the elaiosome, thus reducing it eventually to single 

 seeds. Experiments were also made with a view of 

 establishing the possibility of moUuscan dispersal of 

 single seeds over a short distance. Observations in 

 nature, and on captive Helix aspersa, point to the 

 conclusion that the elaiosome offers an attraction as a 

 molluscan dainty in the way of food. Experiments in 

 the open do not support the idea of the larval re- 

 semblance being an adaptation to ornlthochory, or that 

 there is any regular dispersal by the birds of the neigh- 

 bourhood. Observations and experiments with the 

 ants, Donisthorpea nigra and Myrmica laevinodis, 

 prove that they carry off whole masses, fragments, 

 and single seeds, and take them into the nest. On the 

 other hand, their behaviour does not favour the sug- 

 gestion that the larval " mimicry " is operative, so far 

 as they are concerned. The claim to myrmecochory 

 is not a valid one. So far as the ants are concerned, 

 neither the larval resemblance nor the massing brings 

 to the species any advantage which it would not 

 possess if the seeds were shed singly, as is usually, 

 if not universally, the case with those that are adapted 

 to these insects. The larval resemblance, which 

 cannot be denied, suggests an adaptation to some 

 still unrecognised agent or agents, and observations 

 at the distributional headquarters of the species are 

 much to be desired, in order to clear up the mystery of 

 the mass. 



Manchester. 



Literary and Philosophical Society, November 30. Prof. 



S. J. Hickson, president, in the chair. — Prof. 

 G. Elliot Smith : Further notes on pre-Columbian re- 

 presentations of the elephant in America. An amplifi- 

 cation of the letter published in Nature of November 

 25 (P- 340)- Further examples of representations of 

 the elephant were shown ; and attention was directed 

 to the fact that the Hindu god Indra, who was asso- 

 ciated with the elephant, killed Vritra, who kept the 

 rain in the clouds, just as the Central American 

 elephant-headed god stood upon the head of the ser- 

 pent, who prevented the rain from reaching the earth. 

 NO. 2409, VOL. 96] 



— T. A. Coward : A change in the habits of the black- 

 headed gull. Owing to the remarkable increase in its 

 numbers since the Wild Birds' Protection .\ct of 1880, 

 this gull has extended its range inland, and it is now 

 an inland as well as a shore bird. This increase, in 

 north Cheshire, has resulted in a noticeable change of 

 habit, secondary to the change mentioned above, for 

 within the last few years the bird has been roosting 

 nightly on the waters of Rostherne Mere during 

 autumn, winter, and early spring. Normally, the 

 roosting' and feeding hours of a bird which feeds upon 

 the coast are regulated by the tides, but these Cheshire 

 birds retire to roost like any other diurnal bird, about 

 sundown. The area which these regular diurnal feed- 

 ing and nocturnal sleeping black-heads frequent is 

 contiguous to an area where others of the same species 

 feed and sleep according to the constantly changing 

 hours of the tide in the neighbouring Mersey estuary. 



Dublin. 

 Royal Irish Academy, December 13. — Sir John Ross 

 of Bladensburg, vice-president, in the chair. — H. 

 Ryan and J. Algar : Studies in the diflavone group. 

 in. — Derivatives of dicoumaranone and of diflavanone. 

 Dianisylidenediacetoresorcinol, which was prepared by 

 condensing anisaldehyde with diacetoresorcinol, was 

 converted into its diacetatetetrabromide. Alcoholic 

 potash converted the latter compound into dianisyiidene- 

 dicoumaranone, instead of forming, as might be ex- 

 pected, di-/>-methoxydiflavone. In the presence of 

 alcoholic hydrochloric acid dianisylidenediaceto- 

 resorcinol interacted with anisaldehyde to form anisyl- 

 idene -2-p- methoxycinnamoyl - 3-hydroxy-4'-methoxy- 

 flavanone, and also dianisylidene-4 : 4'-dimethoxy- 

 diflavanone. — H. Ryan and M. J. Walsh : Studies in the 

 diflavone group. IV. — Diveratrylidenedicoumaranone. 

 By condensing veratric aldehyde with diacetoresorcinol 

 a crystalline solid (diveratrylidenediacetoresorcinol), the 

 constitution of which resembles somewhat that usually 

 attributed to curcumindimethyl ether, was obtained. 

 Unlike curcumin, however, the substance can scarcely 

 be regarded as a mordant dye. It formed a crystalline 

 diacetate, which readily added on bromine, and the 

 product, on warming with potash, gave diveratrylidene- 

 dicoumaranone. — H. Ryan and Miss G. Plunkett : Un- 

 saturated /3-diketones. III. By the condensation of 

 veratrylideneacetone with dimethyl oxalate a diketone, 

 3 : 4-dimethoxycinnamoylpyruvic methyl ester, was ob- 

 tained. It formed an tsooxazole and a benzeneazo- 

 derivative. Gentle hydrolysis converted it into the 

 corresponding acid. The substances are mordant dyes, 

 and, w'ith mordanted w'ool, give colours verv similar 

 to those got with curcumin, the dimethyl ether of 

 which they probably resemble in constitution. — H. Ryan 

 and Miss A. Devine : The condensation of aldehydes 

 with ketones. 1 1 1 . — .Aldehydes with methyl-ethyl-ketone. 

 a-Benzylidenemethyl-ethyl-ketone reacts with benz- 

 aldehyde in the presence of aqueous alkali to form a 

 crystalline compound, CisH.gO,, which melts at 83-86°. 

 It, as ^e\l as a-benzylidenemethyl-ethyl-ketone, inter- 

 acts with benzaldehyde in the presence of alcoholic 

 hydrochloric acid to form a colourless crystalline solid, 

 C^HjoO, which melts at 156° C. The latter com- 

 pound may also be got by the action of excess of ' 

 iDenzaldehyde on methyl ethyl ketone in the presence of 

 alcoholic hydrochloric acid. a-Benzylidenemethyl-ethyl- 

 ketone reacts with anisaldehyde and with piperonal to 

 eive the crystalline compounds C2,H340,, and 

 CjrHjoO, respectively, and al,so one molecule of methyl- 

 ethyl-ketone condenses with piperonal to form a crystal- 

 line solid which has the formula C;.Hj„0,. The com- 

 pound C,,H,,0, forms an oxime, but the compound 

 Cj^HooO forms neither an oxime nor a phenyl- 

 hvdrazone. With excess of bromine it gives a di- 

 bromide. C,,H,„OBr,. 



