Jan, 25, 1877J 



NATURE 



273 



LETTERS TO THE EDITOR 



\The Editor does not hold himself responsible for opinions expressed 

 by his correspondents. Neither can he undertake to return, 

 or to correspond with the ivriters of, rejected manuscripts. 

 No notice is taken of anonymous cot?imunications.'\ 



Holly Berries and Rare Birds 



With reference to the statement which has been made by Mr. 

 McNab of the Botanic Gardens in Edinburgh, corroborated by 

 Mr. Darwin and others in England, that holly berries are, this 

 season, extremely scarce, it may be interesting to note that so far 

 as this district is concerned, the holly is, on the contrary, un- 

 usually rich in fruit. For many years I have never seen so 

 abundant a crop, and I suspect this will be found to be the case 

 all over the West Highlands. 



We have had a most unusual winter, from its extreme mild- 

 ness, skies almost continually densely overcast, and the persist- 

 ence of east wind. The rainfall for 1876 was not much in 

 excess of our average — fifty- three inches. We have had little 

 snow, and only one severe gale of wind. But the barometer 

 has been frequently very low, in sympathy with the destructive 

 gales both to the north and to the south of us. 



I don't know whether it is due to any of those circumstances 

 of climate that we have had two very rare birds— the great grey 

 shrike, and the greater spotted woodpecker. 



The shrike was seen here about twelve years ago, on one 

 occasion ; and a specimen of the woodpecker was killed about 

 fifty years ago. About the time when the shrike was seen here 

 on the last occasion, several specimens were shot in different 

 parts of the low country ; but this winter I have seen no case 

 mentioned of the bird being observed. Argyll 



Inveraray, January 20 



On the Southern Tendency of Peninsulas 

 The attention of those interested in physical geography has 

 long been attracted to the remarkable fact that almost all the great 

 peninsulas of the earth trend southwards, and that the majority, 

 at any rate, have an island, or group of islands, at their southern 

 extremity. Thus Mrs. Somerville, calling attention to this, says : 

 — " The tendency of the land to assume a peninsular form is very 

 remarkable, and it is still more so that almost all the peninsulas 

 trend to the south, circumstances that depend on some unknown 

 cause whioh seems to have acted very extensively. The con- 

 tinents of South America, Africa, and Greenland, are peninsulas 

 on a gigantic scale, all directed to the south ; the peninsula of 

 India, the Indo-Chinese peninsula ; those of Korea, Kamtchatka. 

 Florida, California, and Aliaska, in North America ; as well as 

 the European peninsulas of Norway and Swedeii, Spain and 

 Portugal, Italy and Greece, observe the same direction. . . . 



" Many of the peninsulas have an island, or group of islands 

 at their extremity, as South America, which is terminated by the 

 group of Tierra del Fuego ; India has Ceylon ; Malacca has 

 Sumatra and Banca ; the southern extremity of Australia ends in 

 Tasmania, or Van Diemen's Land ; a chain of islands runs trom 

 the end of the peninsula of Aliaska ; Greenland has a group of 

 islands at its extremity ; and Sicily lies" close to the southern 

 termination of Italy." 



Now may we not correlate this with the remarkable prepon- 

 derance of ocean in the southern hemisphere, which M. Adhemar 

 has suggested to be due to the alteration ot the centre of gravity 

 of the earth, caused by the great southern cupola of ice ? How- 

 ever that may be, the preponderance of water in the south is 

 very remarkable. Taking each parallel as unity, the proportion 

 of sea is as follows : — 



Without at the present moment entering upon any discussion 

 as to the cause which has produced this remarkable result, the 

 fact at any rate seems to throw some light on the southern direc- 

 tion of promontories, for which, as far as I am aware, no cause 

 has yet been suggested. For let us suppose three tracts of land, 

 each trending north and south, each with a central backbone, 

 but one with a general slope southwards, one with a northward 



slope, and the third without any. The first will, of course, 

 form a peninsula pointing southwards, because as we proceed 

 southwards, less and less of the surface will project above the 

 water, until nothing but the central ridge remains. The second 

 tract, however, would also assume the same form, because, 

 though by the hypothesis the land does not sink, still the gradual 

 preponderance of water would produce the same effect. 



If, moreover, the central mountain ridge, as is so generally the 

 case, presents a series of detached summits, the last of such ele- 

 vations which rises above the water level will necessarily form 

 an island, situated, with reference to the land, like those men- 

 tioned by Mrs. Somerville. 



Lastly, in the third case, the gradual diminution of water 

 would tend to neutralise the effect of the slope, and if the two 

 were equal, the land would form, not a pointed peninsula, but 

 an oblong tract. 



If there is anything in the above suggestions it will throw some 

 light on the southern trend of peninsulas by bringing them under 

 the general law to which is due the remarkable preponderance 

 of ocean in the southern hemisphere. John Lubbock 



Down, Kent 



Basking Shark 



In looking over some old numbers of Nature, which I had 

 not been able to read, owing to my absence from Florence, I 

 came across Dr. E. Perceval Wright's interesting article on the 

 basking shark, Selache maxima (Nature, vol. xiv. p. 313), 

 which I read with much pleasure, and on which I would beg to 

 offer a few observations, which I hope will not be considered 

 as coming too late. 



First and foremost. Dr. Wright in justly lamenting the absence of 

 information on a most strange and singular form ot Elasmobranch 

 fish, far from being rare on the British coasts, entirely omits to 

 mention the exhaustive and most important memoir on the genus 

 Selache, published by Prof. P. Pavesi, of Pavia, in the Annali 

 del Museo Civico di Storia Naturale di Genova, edited with so 

 much ability, and mostly at his own private expense, by my 

 friend, the Marquis G. Doria. In Italy we usually take much 

 pains to be aujour of foreign scientific literature, and we are 

 striving to do our best to form a good scientific literature of our 

 own, therefore we may be excused if we feel anxious that it 

 should be more generally known and appreciated abroad. Doria's 

 Annali include most important zoological papers, and form 

 already eii^ht big volumes, which have cost the editor no small 

 amount of pains and money ; and it is most desirable that they 

 should not escape the notice of working zoologists out of Italy. 

 Indeed I may refer to some of the leading English zoologists, 

 and more especially to my friend Dr. P.- L. Sclater, to cor- 

 roborate my assertion. 



Prof. Pavesi's paper, " Contribuiione alia Storia Naturale del 

 genere Selache," is continued in the sixth volume of Doria's 

 yf««a/;, published in 1874; and had Prof. Wright read it, he 

 would have discovered that the very conflicting opinions on 

 Selache, Polyprosopus, and Pseudotriacis had been most carefully 

 examined, discussed, and sifted, that all the anatomical and 

 zoological labours of well known and little known savants on 

 the subject had been carefully analysed and critically studied by 

 Prof. Pavesi, who in illustrating in a very lucid and minute 

 manner the zoological affinities and anatomical peculiarities of a 

 fine specimen of Selache captured at Lerici, near Spezia, on 

 April 25, 1 87 1, has succeeded in solving the Gordianknot which 

 confused the true relations of the three genera above cited, and 

 refers those strange Selacoids to two forms : Selache maxima 

 (Gunn) and S. rostrata (Macri). To the latter species, character- 

 ised by a most singular snout, is to be referred the Lerici speci- 

 mens, now in the Museum of the University of Genoa ; one 

 captured near Reggio (Calabria) in May, 1795, and described 

 by Macri as Squalus rostratus ; and lastly, the basking sharks, 

 captured on the Western British coasts, and described in an 

 incomplete manner as Polyprtsopus by Couch, and as Squalus 

 or Cetorhinus rostratus by Cornish. 



Prof. Pavesi has largely illustrated the anatomy oi S. rostrata 

 in his memoir, especially the skeleton of the Lerici specimen 

 which is preserved entire in the Genoa Museum; he also 

 describes and figures the strange baleen-like fringes which adorn 

 the branchial arches. Henry J. GiGLloLi 



Florence 



[We have also received a communication from Rev. M. 

 Harvey, of St. John's, Newfoundland, mentioning that a spe- 



