December 12, 1895] 



NATURE 



129 



As a matter of fact, any one who will take the trouble to read 

 Dr. Calmette's papers and Prof. fVaser's, will find that the sole 

 credit of discovery in this matter rests with Dr. Calmette, who 

 worked under the direction and with the suggestions of Dr. 

 Roux. 



It would be interesting to know whether the Annales de 

 rinstitut Pasteur are accessible to Prof. Fraser, and whether 

 he thinks that his vague reference to Calmette's detailed 

 researches, and his designation of the interval between May 

 1894 and June 1895, as " a few months," are calculated to give 

 to the British public a fair notion of the merit in this matter of 

 his French colleague. E. Ray Lankester. 



Oxford, November 38. 



The Maerjelen Lake. 



A cORRESi>(iM)KN(E which I was recently the innocent cause 

 of initiating in the Standard, revealed a very remarkable 

 conflict of evidence touching the question of how often and to 

 what extent the Maerjelen Lake^ has of late years emptied 

 itself. As I pointed out, the rare phenomenon of a total 

 discharge of -the lower basin through the Aletsch glacier 

 recurred last September ; whilst in the great majority of cases, a 

 pool more or less deep is left in that basin, and the upper, more 

 shallow basin is never quite empty. 



Considering the grandeur of the emptying of the lake as an 

 Alpine phenomenon, it might reasonably be expected that those 

 who are fortunate enough to witness it, would take the trouble to 

 note the dates and facts accurately. Such, however, is rarely the 

 case, for many eye-witnesses are so led away by their enthusiasm 

 at the time, and so deceived by their memory afterwards, that their 

 evidence is often flatly contradictory, and hence of little or no 

 value. This is strikingly illustrated by the public correspondence 

 referred to, as well as by private letters and other information I 

 have received since. 



It would lead too far to enumerate all the vague and con- 

 tradictory statements, both as regards dates and facts. Suffice it 

 to mention that, while somc^ye-witnesses infer a total emptying 

 of the lake simply from havmg seen a rush of water along the 

 surface of the Aletsch glacier, others draw the same inference 

 from the fact that they saw the lake empty. But neither of 

 these inferences affords proof of a total discharge ; for in the 

 first case, only a partial discharge may haive taken place, such as 

 last occurred in September 1894, and in the second case, the 

 lake, unless it was seen full the day or a few days before, may 

 have been partially or completely empty for months. A partial 

 emptying is of frequent occurrence ; but the only true test of a 

 total discharge, as authentically recorded, e.g. in 1864, 1878, 

 1887, and 1895, is the exposure of the glacier wall to its full 

 depth of at least 150 feet immediately after the event. Some 

 years ago. Prof. F. A. Forel gave a list of the recorded discharges 

 (without special reference to partial or total discharges) up to 

 1890) ;- but even that list cannot, and, I believe, does not lay 

 claim to completeness and strict accuracy. 



The occurrence of September this year is of peculiar interest, 

 because it shows that, notwithstanding the recently completed 

 artificial overflow tunnel to the Viesch glacier, the Maerjelen 

 Lake prefer^ its old outlet through the Aletsch glacier. 



C. S. Du RicHE Preller. 



The Former Northward Extension of the Antarctic 

 Continent. 

 I SHOUi.i) not presume to draw the attention of your readers 

 to this much-discussed topic without having a new fact to con- 

 tribute. The opportunity of loading still further the already 

 overweighted scale which now dips so deeply in favour of the 

 notion of a former northward extension of the Antarctic con- 

 tinent, has been afibrded me by the kindness of Prof. Parker, 

 F.R.S. ,of Otago, New Zealand. He has forwarded to me a 

 few worms collected in Macquarie Island, which lies to the south 

 of New Zealand, about half-way between it and the land of the 

 southern continent. These belong partly to the almost world- 

 wide Fachydrilus, and one species— a new one — is referable to 

 the earthworm genus Acanthodrilus. The imiiortance of this 

 latter species is that it is firstly an Acanthodrilus, and secondly 

 that it is closely allied to a group of Patagonian and South 

 Ceorgian species of the same genus, and is less like any New 



1 Vide Nature, 1887, vol. xxxvi. p. 612. T. G. Bonney. 



2 " Variations Piriodiques des (Slaciers des .Alpes." S. A. C. 1890, p. 358. 



Zealand form. It is to me a matter of surprise that Dr. H. O. 

 Forbes, in his recent and important essays upon this (juestion, 

 has ignored the distribution of earthworms, which are so 

 thoroughly wedded to the soil, and (except in a few cases) so 

 impatient of sea-water. I have attempted to rectify this state of 

 affairs in a text -book of zoogeography, lately issued by the Cam- 

 bridge University Press. In Patagonia and some of the islands 

 immediately to the southward, only two genera of indigenous 

 earthworms, so far as is known at present, exist. These are 

 Acanthodrilus and Microscolex. Of the former there are nine 

 species, and of the latter five ; but five species of Microscolex 

 and two species of Acanthodrilus, in addition to those referred 

 to, range northwards into Chili, which zoologically is indis- 

 tinguishable from Patagonia. Let me emphasise the point that 

 these are the only two genera which occur in these latitudes, 

 save for a species or two of the European Allolobophoba, which 

 is universal in range — thanks probably to direct exportation by 

 man. In Kerguelen and Marion Islands but one species of 

 earthworms has been found, which is an Acanthodrilus. In New 

 Zealand there are nine species of Acanthodrilus, also six species 

 belonging to genera that are very nearly akin to Acanthodrilus, 

 and three species of Microscolex. The remaining six species of 

 Microscolex are South and Central American to the extent of four, 

 while the two remaining are from Tenerife and Algeria. Of 

 Acanthodrilus, the only species left, after deducting those 

 already enumerated, are one from the Cape of Good Hope, one 

 from New Caledonia, and three from Western and North 

 Australia. Besides these forms New Zealand possesses a single 

 Perichretid worm and Schmarda's species, Hypogieon orthostichon, 

 which I have recently (a " Monograph of the Order Oligochseta," 

 Oxford, at the Clarendon Press) referred to the characteristically 

 Australian genus Megascolides. It is clear that, if the former 

 northward extension of the Antarctic continent is not believed, 

 some explanation of these remarkable facts is much wanted ; on 

 that hypothesis they are perfectly explicable. 



Frank E. Beddard. 

 Zoological .Society's Gardens. 



The Feeding Ground of the Herring. 



I have no desire to set aside lightly the observations of 

 Profs. Herdman, Brady, Scott, or any other scientific gentleman, 

 as suggested by Mr. Calderwood in your issue of November 21. 

 There is no evidence that these gentlemen have made any 

 systematic examination of the deep waters of Loch Fyne, 

 whereas I have carried out investigations of this kind during 

 many years at all seasons under the direction of Dr. Murray and 

 Dr. Mill, and I think Prof. Herdman set these observations very 

 lightly aside in his Ipswich address. 



If various kinds of tow-nets be dragged through the surface 

 waters of Loch Fyne, down to a depth of 20 fathoms, at the 

 present time of the year, probably not a single specimen of red- 

 coloured Calanus, Eiichivta, Nyctiphanes, or Boreophausia, will 

 be captured, and these animals I hold make up nine-tenths of the 

 bulk of the food of the herring in Loch Fyne. If the same 

 nets be dragged near to the mud at the bottom in depths 

 between 70 and 100 fathoms, immense numbers of these 

 Crustaceans will be taken ; and this state of matters practically 

 holds good throughout the whole year, these Cru.staceans being 

 always found at the bottom and rarely at the surface. It 

 occasionally happens, however, that at quite local spots some of 

 these deep-sea Crustaceans rise or are drawn up to the surface, 

 and being carried out of their natural habitat are killed there, 

 and are blown upon the shore, where they form a red line along 

 the beach. It must be remembered, however, that this is quite an 

 exceptional occurrence. On several occasions we wished to 

 send to Inveraray living specimens o\ Nyctiphanes, in order that 

 their brilliant phosphorescence might be exhibited. These were 

 captured in large numbers in the trawl sent down to 70 fathoms, 

 but we found that they were all killed as soon as they were put 

 into the jars, which we afterwards found had been filled with the 

 somewhat fresh water floating on the surface of the loch ; it was 

 only by collecting water from the deeper layers that a few speci- 

 mens could be preserved alive. On other occasions, after a long 

 spell of dry weather, there was no difficulty in keeping large 

 numbers of Nyctiphanes alive for a long time, and on one 

 occasion I conveyed many bottles filled with these Crustaceans 

 to Edinburgh,^ and exhibited them at an evening-meeting of the 

 Royal Society. 



The very fact that Mr. Calderwood was able to scoop up red- 



NO. 1363, VOL. 53] 



