May 



[894] 



NA TURE 



lower molars of the tubercular-sectorial types • ; in fact, I think, 

 we cannot do better than accept Prof. Cope's generalisation, - 

 if not as a definitely established theory, at all events as an 

 excellent working hypothesis, "that the superior molars of both 

 ungulate and unguiculate mammalia have been derived from a 

 triiubercular type ; and that the inferior true molars of both have 

 been derived from a lubercular-seclorial type." These, in- 

 deed, are the types which occur most constantly amongst the 

 earlier fossil forms, and the most primitive living representatives 

 both of the Marsupials and Placentals. The Pro-mammalia, 

 when they first arose as a small group struggling amongst their 

 reptilian and amphibian rivals, very possibly adopted some 

 method of feeding for which teeth of these or similar patterns 

 were well adapted. Subsequently, with increasing number and 

 divergence, just as in the pentadactyle limb some digits have 

 been lost and others become unduly developed, the tritubercular 

 teeth have been modified to suit various needs; with this 

 difference that, although digits are not easily added, new cusps 

 often have arisen in the course of adaptation. 

 Oxford, April 21. £. S. Goodrich. 



Zoological Regions. 



With reference to the paper of Mr. Wallace in N '.TURE 

 ^vol. xlix. page 610), I agree with Mr. Wallace's aim and with 

 his estimate of the importance of the subject. 



A naturalist, who deals with a single large genus as Pedicularis, 

 makes his own map, showing the distribution of the species and 

 his own view of the lines of descent of his sections in geologic 

 periods. He cannot do this on a map showing the division of 

 the world into six biologic regions according to the Mammalia 

 in them. Or, at all events, none of our monographers, so far as 

 I know, has done it. The difliculty in dealing with a whole 

 natural order is still greater. 



The consequence is that, if some other botanic writer wishes 

 to compare the distribution of Pedicularis with that of some 

 allied genus, or to give a view of the distribution of the sub-order 

 1 to which Pedicularis belongs, he cannot make any use of the 

 results of the Pedicularis monograph without taking it all to 

 pieces and re-arranging the whole material. This is in every 

 case a laborious, in many cases an impossible task. 



I therefore agree with Mr. Wallace that we require a 

 division of the globe into "areas absolutely defined, easily 

 I remembered," so that, after the monographer has treated his 

 genus or order in natural regions, he may also " tabulate " his 

 (acts on thtse standard areas ; in order that his numerical results 

 may be (at least in the rough) accessible (or immediate use by 

 'liL-rs who may not have time (or sufficient special knowledge) 

 1 I i;et up the monograph. 



it is evident that Mr. Wallace has overlooked my paper on 

 biologic regions and tabulation areas in Trans. Linn. Soc. vol. 

 clxxxiii. [1892] (15) pp. 371-387. Otherwise he could hardly have 

 written (Nature, vol. xlix. p. 612) that his regions readily enable 

 us to tabulate the distribution of a group (and many other state- 

 ments). In my paper I have pointed out that where I know, as 

 in the case of many Sikkim plants, the exact boundary line of 

 distribution of many species, I cannot tell whether these should 

 be tabulated in Wallace's Region I, or in his Region 3, or in 

 both. The number of species which are in this predicament is 

 so great that by exerting a choice how I would tabulate them I 

 could bring out any result that might be wished. The more 

 accurately I know the distribution of a species the more impos- 

 sible is it for me to tabulate it on Wallace's map. And the more 

 perfectly a region is biologically laid down (with peninsulas, 

 islands, &c. ) the more impossible it is to use it as an " area " for 

 tabulating on. Hut, I must not trouble you with a recapitula- 

 tion of my paper above cited, to which I refer Mr. Wallace and 

 others who may be interested. C. 13. Clarke. 



Ivew, April 30. 



The Earthquakes in Greece. 



The severe earthquake felt in Greece on April 27 at 9.20 

 p.m. was observed in Birmingham by the aid of a delicate 

 bifilar pendulum, with which observations are now being made 



t In .1 former paper, '* On llie Fossil Mammalia from the Stonesfield 

 Slate" {Quart. Jour. Micr. Sci. xxxv. 1894), I brought forward some 

 additional evidence in favour of this theory. 



- "On the TrituberculateType of MoIarTooth in thfi MammaH.l" {Proc. 

 Jtm. Phil. ivc. iSS)), and "Origin of the Fittest." 



on behalf of the Earth Tremor Committee of the British Asso- 

 ciation. This instrument, designed by Mr. Horace Darwin, and 

 made by the Cambridge Scientific Instrument Company, is de- 

 scribed in the Report of the Committee presented at the Not- 

 tingham meeting last year." I may merely mention here that a 

 tilt of the ground in an east-west direction is magnified about 

 3000 times by the rotation of a miiror about a vertical axis ; 

 and that the image of a fine wire in front of a movable gas- 

 jet, after relleclion by the mirror, is observed in a fixed telescope 

 in the passage outside the cellar in which the pendulum is 

 erected. 



Shortly before 8 p.m. (Greenwich mean time), I went down to 

 take the usual reading, and found the image of the wire moving 

 slowly from side to side of the field of view, showing that the 

 ground was rocking gently backwards and forwards, the time 

 of a complete pulsation being from twelve to fourteen seconds. 

 It was difficult under the circumstances to make any exact 

 measurements, but the maximum east-west component of the 

 tilting cannot have been less than a quarter of a second. The 

 pulsations were first observed at 7h. 59ni., and my impression 

 is that the range slightly increased until 8h. 3m. It then rapidly 

 diminished, being about ,'„ of a second at 8h. 12m., and never 

 less than ^J,t of a second until 8h. 28m., after which the pul- 

 sations ceased to be perceptible. 



The time given by the newspaper correspondents is, I sup- 

 pose, Athens time, and corresponds to yh. 45m. Greenwich 

 mean time. The interval between the occurrence of the earth- 

 quake and the arrival of the pulsations in Birmingham was 

 uierefore not greater than 14m., and, the distance traversed 

 being roughly 1550 miles, it follows that the average velocity of 

 the pulsations cannot have been less than i '84 miles per second. 



Gillott Road, Birmingham, May i. C. Davison. 



" Vermes." 



I WISH to enter a protest against the continued use of the 

 word " Vermes " as a teim of systematic significance with the 

 same value as " Mollusca," " Arthropoda," &c. Linnaeus 

 used ihe term to include all soft-bodied invertebrates — i.e. 

 sveiything then known except the Arthropoda (his " Insecta") 

 and Veitebrata. Then Lamarck employed the word in a much 

 more definite and unexceptional sense, to include the parasitic 

 woims, ihe Cljetopoda being separated as "Annelida." But 

 what do modern writers meant by "Vermes"? Why, it has 

 r.early as indefinite a limit as that given to it by Linna:us, for it 

 is used to include almost <!;y invertebrate animal — nevermind 

 its structure — which does not fit in the Mollusca, Arthropoda, 

 Echinodei ma, Ccelentera, or Protozoa. In fact, the term, asem- 

 ployed in such authoritative publications as the Zool. Kicord, 

 Zool. Jalirabericlit, &c. , as well as by Jackson in " Forms of 

 Animal Life," and in Lang's text-book, &c., embraces all, or 

 most, of the following groups of animals :— Cestoda, Trema- 

 toda, Planaria, Nemertina, Aich'annelida, Chxtopoda, Hiru- 

 dinea, Gephyrea, Polyzoa, Brachiopoda, Nemaloda, Acaniho- 

 cephala, Rotifeia, Sagitta, Echinodeies, and sundry other 

 small worm-like forms, and even Balanoglossus, and occasionally 

 ChKlodeima and Neomenia. 



1 do not intend to enter into the classification of this hetero- 

 geneous assemblage of forms, nor need I do more than refer to 

 the fact that definite terms with scientific limit.ations are in 

 existence under which the members of the assemblage can be 

 (and are) grouped. 



I am perfectly ready to admit that "Vermes" may be a 

 useful descriptive term, if used to imply a certain general form 

 of body, as opposed to some other groups ; but I do wish to 

 urge the abolition of it from text-books or titles of papers by 

 well-known zoologists. That the eradication of the word 

 presents considerable difficulties, I am aware ; since it is not in 

 Kngland alone that " Vermes " still holds sway, but in all the 

 European countries the equivalents "Vers," or " Wiirmer, " &c. , 

 are employed with a more or less equivalent indefiniteness. 

 Nevertheless, several such terms/dji^f been abolished, and no one 

 nowadays would think of speaking, even in a popular, still less 

 in a scientific work, of " Radiata " or "Zoophytes" or "In- 

 fusoria," in the antique significance of these words. 



Oxford, April 18. Wm. Bla.xland Benham. 



I An account of a new and improved form of the pendulum will appear 

 shortly in Nature, 



NO. 1279, VOL. 50] 



