HARDWICKE'S SCIENCE-GOSSIP. 



21 * 



considered entirely of Tebidian age, as there is no 

 evidence that the Dimetian rocks are exposed there. 

 Afterwards, Professor Hughes read a paper on the 

 Precambrian rocks of Bangor, which consist of slates, 

 agglomerates, and porphyritic rocks ; and these, he 

 thinks, are equivalent to Dr. Hicks's " Pebidian." 



Palmam qui meruit. — The Royal Society of 

 England have just awarded Professor James D. 

 Dana, the distinguished American mineralogist and 

 geologist, their highest honour, the " Copley Medal." 

 The "Royal Medal" went to Professor Heer, the 

 equally distinguished fossil botanist, of Zurich. 



A Fossil Fungus. — A very interesting article in 

 your last number, which is headed " A Fossil 

 Fungus," refers to the discovery of a fossil fungus 

 in Lepidodendron, by Mr. Carruthers, and its subse- 

 quent study and classification by Mr. Worthington 

 Smith. It is there stated: "This is, perhaps, the 

 oldest fungus on record. " As this is not quite correct, 

 I beg to inform you that in 1858, C. Wedl found 

 something very much like Saprolegnia ferox in a 

 Leptiena from the Devonian. In May, 1876, I read 

 a paper before the Geological Society, in which 

 unicellular algoe were described parasitic within a 

 foraminifer from the Lower Silurian, a coral from 

 the Upper Silurian, in brachiopods, and corals from 

 the Devonian, and from a coral in the Miocene. 

 I named and figured this penetrator Palceachlya 

 pcrforans. In the Proceedings of the Royal Society, 

 No. 174, 1876; I explained the physiology and 

 morphology of AcJilya penetrans, now found in 

 recent corals and shells, and explained the life 

 cycle of this saprolegnions plant, so that, from its 

 almost complete resemblance with the ancient form, 

 it could be considered its descendant. The septa, 

 which are said not to occur in the mycelium of 

 Saprolognia are really seen very rarely, but still they 

 do exist. — P. Martin Duncan. 



Erratum. — In my last paper on the Carboniferous 

 Polyzoa, December 1S77, the reader will oblige by 

 correcting the following : page 272, 8th line in list, 

 G. flesicajinala read G. flexiearinata. Page 273, 

 1st col., nth line from top, for "genus" read 

 " familv. "—C. R. V. 



NOTES AND QUERIES, 



The Pairing of Birds. — Is it sufficient proof of 

 birds pairing for life, that we find the old nests 

 tenanted year by year ? Some birds are known to 

 use the old nests of other species ; e.g. , the House 

 Sparrow, which is one of the species which, upon this 

 evidence, Mr. Dixon quotes as pairing for life, 

 frequently uses the old nests of the House Martin ; 

 and if of other species, why not of the same species ? 

 I fail to see why Mr. Dixon supposes that polygamy 

 tends to prolificness : it can only do so if the number 

 of females born, or arriving at maturity, be in excess 

 of the males. Among mankind, as men and women 



arrive at adult age in about equal numbers, if one 

 man have two wives, another must go without one, 

 and it is obvious that both the procreative power, and 

 what is probably of more importance, the power to 

 maintain offspring of two males, will be greater than 

 that of one male. Polygamy can only tend to a 

 more rapid increase of population where the number 

 of females is much in excess of that of males, either 

 through female immigration, as in the Mormon settle- 

 ments, or, as more usually happens, through the 

 greater mortality of males. It is hard to believe that 

 nature has been so considerate to mankind as to make 

 fowls polygamous in order that the superfluous males 

 may afford us food. It seems more reasonable to 

 suppose that the habit of polygamy is in some way 

 advantageous to the polygamous species itself. 

 Polygamous animals are usually provided with special 

 weapons of offence, like the cock's spur, and are in 

 the habit of fighting for the females : the strongest 

 and best-armed male wins the largest number of fair 

 prizes, and the progeny of such a male are likely to 

 have the advantage over their competitors in the 

 struggle for existence. It does not seem difficult to 

 explain why species which are monogamous in the 

 wild state should be polygamous in captivity. Given 

 an excess of females over males, and in the absence 

 of social and moral restraints, polygamy follows as a 

 matter of course. — H. F. Parsons, M.D. 



Pairing Instincts of Birds. — If birds returning 

 to their old nests is a sign that they pair for life, 

 I may add to Mr. Dixon's list the Blackbird ( Tnniits 

 mcrula), for a nest has been occupied successively for 

 the last three years by a pair of these birds. Now as 

 there are two or three other nests in the same hedge, 

 I think it must be the same pair that has successfully 

 reared three broods in the one nest. Perhaps 

 Mr. Dixon— since he has been observing particularly 

 the pairing instincts of birds — could kindly give me 

 some information as to one species of bird pairing with 

 anather (see Science-Gossip, p. 263). I have known 

 instances of hybrid grouse, but never of a hybrid 

 between a blackbird and a thrush. — G. F. B. 



Mites in a Collection of Lepidoptera. — In 

 reply to the query in the December number of 

 Science-Gossip I beg to say that, having had the 

 misfortune to find mites in my collection of Lepido- 

 ptera, I was recommended to try naphthaline, and so 

 far as I am at present able to perceive, no further de- 

 struction has taken place since I used the same. I put 

 the naphthaline in a small pill-box with a perforated 

 lid, which is glued into the corner of the drawer, and 

 does not attract attention. Any insect specially 

 affected should be removed from the cabinet or store- 

 box and carefully painted on the thorax with corro- 

 sive sublimate. — A. J. R. 



Destroying Mites on Lepidoptera. — In 

 answer to "A. F.'s " query on this point, let me draw 

 his attention to the following extract from Mr. 

 Newman's preface to his splendid work on British 

 Butterflies and Moths : — " Directly you observe any 

 dust, however little, underneath an insect, .... 

 take out the infected individual ; as soon as he is 

 removed from the drawer, drop benzole on his back, 

 drop after drop, until he is thoroughly saturated, and 

 all his wings are rendered perfectly transparent. In 

 this state remove him to the drying-cage, and there 

 let him remain until all the benzole has evaporated, 

 and his colours have returned, bright and beautiful as 

 ever." I have not tried this method myself, but I 

 have friends who have, and they find it to answer 

 perfectly. — W. J. B. 



