XII] or THE FORAMINIFERA 871 



within its own lifetime is hfeld to be at least a partial recapitulation 

 of the unknown history of its race and dynasty* 



We encounter many difficulties when we try to extend such 

 concepts as these to the Foraminifera. We are led for instance to 

 assert, as Rhumbler does, that the increasing complexity of the 

 shell, and of the manner in which one chamber is fitted on another, 

 makes for advantage; and the particular advantage on which 

 Rhumbler rests his argument is strength. Increase of strength, die 

 Festigkeitssteigerung, is according to him the guiding principle in 

 foraminiferal evolution, and marks the historic stages of their 

 development in geologic time. But in days gone by I used to see 

 the beach of a little Connemara bay bestrewn with millions upon 

 millions of foraminiferal shells, simple Lagenae, less simple Nodosariae, 

 more complex Rotaliae : all drifted by wave and gentle current 

 from their sea-cradle to their sandy grave: all lying bleached and 

 dead: one more delicate than another, but all (or vast multitudes 

 of them) perfect and unbroken. And so I am not incUned to beheve 

 that niceties of form affect the case very much : nor in general that 

 foraminiferal life involves a struggle for existence wherein breakage 

 is a danger to be averted, and strength an advantage to be 

 ensured f. 



In the course of the same argument Rhumbler remarks that 

 Foraminifera are absent from the coarse sands and gravels J, as 

 Williamson indeed had observed many years ago: so averting, or 

 at least escaping, the dangers of concussion. But this is after all 



* A difficulty arises in the case of forms (like Peneroplis) where the young shell 

 appears to be more complex than the old, the jfirst-formed portion being closely 

 coiled while the later additions become straight and simple: "die biformen Arten 

 verhalten sich, kurz gesagt, gerade umgekehrt als man nach dem biogenetischen 

 Grundgesetz erwarten sollte," Rhumbler, op. cit. p. 33, etc. 



f "Das Festigkeitsprinzip als Movens der Weiterentwicklung ist zu interessant 

 und fiir die Aufstellung meiries Systems zu wichtig um die Frage unerortert zu 

 lassen, warum diese Bevorziigung der Festigkeit stattgefunden hat. Meiner 

 Ansicht nach lautet die Antwort auf diese Frage einfach, well die Foraminiferen 

 meistens unter Verhaltnissen leben, die ihre Schalen in hohem Grade der Gefahr 

 des Zerbrechens aussetzen; es muss also eine fortwahrende Auslese des Festeren 

 stattfinden," Rhumbler, op. cit. p. 22. 



X " Die Foraminiferen kiesige oder grobsandige Gebiete des Meeresbodens nicht 

 lieben, u.s.w.": where the last two words have no particular meaning, save only 

 that (as M. Aurelius says) "of things that use to be, we say commonly that they 

 love to be." 



