li. K. UA)\U. - \Ai;i\TI(>,N AMIIM. IIII-; IIATS (iK I.MllA. .M'.i 



l'amily f^roiii) and ol" llie hillcr cxpandiu!^' iiilo ;i sjn'cies. Tliort' is no (loiil)l 

 thaï small t;rou|)S ol' likc animais cxisL in nalnio; liic caise al Rangoon is ono 

 dclinili' cxample of sucii a t;ron|). Sincii' llicy arc so scldom descrilicd lliov 

 apjH'ai- 1(1 bc verv fcw . lînl. il nuisl l)c rciiuMid.ci-cd thaï. \\c oIisci'M' oni\ a 

 niinnle portion uf tlie animal kins^dom and lliat wc makc onr observations in a 

 particular mantici-, \ve do nol know Huit such gi'oups are few : as a rcsull of my 

 ow n oliscrvations ! Iielicvc thaï they are plenliful. l.el us examine tlie ques- 

 lion. .Iiidiiiiig IVom liii! Iinuian population and IVoin Ihc iiunierical |)roportion 

 (iT nicn 1(1 rais in a single town or village, il is sale to say Ihal Ihe number ol' 

 rais in India al any nn)menl is at leasl a liiousand millions. Far more Ihal 

 Ihis are boiii in a year. It is impossible to estimale llie number of rats whicli 

 lune lieen exaniined in Ihe last live years in oi'dei- to tind l'amily gronps, 

 beeause mosi ol' the attention wliich thèse animal hâve reeeived lias Iteen given 

 by the Sanilarian and not by Ihe Biologist, but \ve niay be quile sure thaï the 

 number, il' kno\\n, would be a minute fraction of Ihe number of rats born during 

 Ihe lime of Ihe enquiry. Bul altliough a minute fraction of the mass is ail Ihal 

 bas been examined, yet a considerabh? number of family groups hâve been 

 found aniong il; the Ihree deseribed hère are picked cases. Hence il seenis to 

 me Ihat thèse gr'oups must be [ilenliful. The groups no doid)t vary in nunic- 

 rical si/e, lliey coiilain Iwo, len, a hundrcd members. at Ihe niomenl, as the 

 case may be. 



The l'aie of thèse gron])s musl be Ihal of ail groups of organisms, extinc- 

 tion sooner or laler. Judging froni Ihe cases at Rangoon and Poona \ve may 

 be sure Ihal the duralion of most of thèse groujis is nol more llian a l'ewgene- 

 ralions (of rats , but any group which possesscd a decided ad\anlage, such as 

 immunity from plague, l'or exaniple, wonid persisl foi' many generalions and 

 become very large. 



In my opinion il is unneccssary to discuss vvhclher thèse groups can give 

 rise to species or nol. At any raie the{|uestion cannot be ans^vered unless \\e 

 dedne a species numerically. If \ve define a species as a group of like orga- 

 nisms numbei'ing upwards of a million. Ihen only can \ve know if a sport gives 

 rise lo a species, in any given case. I do nol of course ad vocale the use of 

 snch a définition serionsly, bul the suggeslion may perhaps show Ihe inadequacy 

 ol' llie conception indicaled by Ihe \\ord species. 



A critic may ask, — bow is il llial family groups are not more oflen des- 

 eribed, if Ihey are iilenliful in nature? Tliere is a salisl'actor> l'cply lo tliis 

 ol)jeclion. Such groups ha\i' oflen been iiiel willi. but "•; i/mujjn they bave 

 nol been full deseribed. Under the name of ■ rare species " they hâve found a 

 place among our eslablished conceptions. Il is well known that rare species 

 are \ery plenliful, many writers hâve reniarked Ihe l'acl with surprise, \^'e 

 lind such species espeeially aniong the lerrestrial vcriebrates. Soiiie s])ecies 

 are very rare : Ihey are recorded once bul never agaiii. Olliers are ' rare and 

 local ". They occur al one place and witliin iiarrow liniils. 



Suiiimarij of t/ic forrijiiiiiii. - The conception of species must be bronghl 

 inlo doser agreemeni willi icalily. \l preseni, species are regarded as groups 

 of like organisms, the number of individiials in eacli being indelerminale and 

 Iherefore very large. Hère lies Ihe fallacy. Il is always more casy to deler- 

 iiiiiie llie iiuinl>er of things in a small group than in a large one. and siieaking 

 gi'neially wc may say Ihal immense niimbers of any kind of Ihings are indeter- 



