332 



NATURE 



[May 19, 19 10 



simple reason, overlooked by von Uexkiill, that these 

 anemones are infected by symbiotic algae. 



The effect of wave-action is analysed in a most in- 

 teresting section devoted to the higher medusae. The 

 simpler nature of the muscular reflex in Rhizostoma 

 is first explained. It is shown how contraction of the 

 . circular muscles of the bell-margin, together with that 

 of the stomach-wall, subserves at once locomotion, re- 

 spiration, and nutrition. The food of Rhizostoma 

 (Diatoms) is obtained by filtering the sea-water through 

 the minute pores into which the oral aperture is con- 

 verted. Especially attractive is the contrast in this 

 section between the two allied genera, Rhizostoma 

 and Gonionemus. The first leads a life of one 

 stimulus. The rhythmical pulsation of its bell is its 

 only act, its one stimulus. Gonionenrus, on the other 

 hand, though not structurally very diverse, leads a 

 full life. It responds to light and to darkness, to 

 gravity, to chemical and mechanical stimuli. The 

 same world environs each animal : but an organism 

 is, as it were, a wonder-world shut off from this 

 •environment, and only the right key opens it. When 

 there is no lock there is no key, and such is the plight 

 of Rhizostoma. Gonionemus has many doors, each 

 with its special key. 



From jelly-fish the author passes to the study of sea- 

 urchins, and here he is thoroughly at home, leading 

 the reader through a study of bionomics to an analysis 

 of muscular contraction that is of the greatest import- 

 ance to physiologists. 



Of the author's analysis of the movements of the 

 earthworms, leech, and Sipunculus we have no room 

 to speak, but recommend it to the attention of all 

 physiologically minded biologists; but a word must 

 be said on Jordan's recent work on the locomotion of 

 the mollusc, Aplysia. The body of this creature is 

 enclosed in a muscular sac provided with a thick 

 nerve-network. Each nerve is connected with this 

 diffuse nervous system as well as with the ganglia. 

 The extraordinary thing about the stimulation of this 

 system is that, if the pedal ganglion be stimulated, the 

 effect upon the network and muscular sac is entirely 

 different from that proceeding from the cerebral 

 ganglia. The "brain" inhibits motion; it acts as a 

 brake. These animals, and possibly all Mollusca, 

 resemble such machines as give rise to an e.xcess of 

 steam in all their parts, which excess is allowed to 

 escape by numerous exits. The idea of a group of 

 animals which acts in this way is an entirely novel 

 one. 



The further studies on crabs and dragon-flies are of 

 great interest, and we wish it were possible to repro- 

 duce their conclusions. Enough, however, has been 

 said to indicate the value of this work. If only the 

 nature of the author's views on reflexes were ex- 

 pressed more clearly we should be inclined to place 

 this book among the most attractive, as it certainly is 

 one of the most illuminating, comparative studies that 

 have appeared. It should appeal to the physiologist 

 and psychologist as much as to the naturalist, and if 

 translated (with a glossary appended) would be eagerly 

 read by a much larger public than will appreciate it 

 in its present form. ' F. W. Gamble. 



NO. 2 1 16, VOL. 83] 



SCIENCE AND BELIEF. 



Science and Religion in Contemporary Philosophy. 

 By Prof. Emile Boutroux. Translated by Jonathan 

 Nield. Pp. xi+400. (London : Duckworth and 

 Co., 1909.) Price Ss. net. 



THIS book is an able study of the various attempts 

 which have been made since the beginning of 

 the great scientific movement of the nineteenth 

 century to comprehend science and religion in one 

 system. The writers considered fall into two groups, 

 according as they approach the problem from a 

 naturalistic or spiritualistic standpoint. As repre- 

 sentatives of the former M. Boutroux takes Comte, 

 Spencer, Haeckel, the psychologists and the sociolo- 

 gists. The inclusion of Haeckel was perhaps due 

 to his popularity; his dogmatism and inconsistencies 

 are too crude to be worth thfe attention of an 

 analyst so subtle as M. Boutroux. The discussion 

 of the others might be said to be a discussion of 

 three suggested unifying notions — the notion of 

 humanity, that of the unknowable, and that of fact. 

 The first M. Boutroux finds too narrow, for science 

 refuses to accept an ideal from practical human need, 

 and the essential object of religion is something that 

 is more than man. The concept of Spencer gives 

 liberty at the cost of significance ; M. Boutroux shows 

 very clearly that Spencer was led to it by a false 

 standard of knowledge, the standard of pure objec- 

 tivity, according to which to know the absolute would 

 be to know it as one thing among others. As for 

 the psychologists, who show that the scientific and the 

 religious activities are amenable to common psychic 

 laws, their reconciliation ignores the difficulty, which 

 is the disparateness of the specific ideals inspiring 

 these activities. The sociologists are in no better 

 case ; for the given social ends to which they propose 

 to make religion and science both subservient are 

 being by these continually recreated. 



M. Boutroux 's analysis of the spiritualistic efforts 

 to solve the problem is equally searching. He deals 

 first with the apologists. Some, like the Ritschilians, 

 appeal to immediate internal conviction as the suffi- 

 cient defence for religion ; there are others who, by a 

 criticism of science, show that it is ultimately founded 

 on certain practical beliefs, and contend that science 

 cannot object to religion merely as belief. But the first, 

 since they have discarded all theory, can do nothing 

 but indicate a mere subjectivity, and the second can 

 offer only what appear to be arbitrary beliefs as 

 against the verified hypotheses of science. Next is 

 considered that philosophy which professes to find in 

 activity a principle of unity deeper than the level of 

 our intellectual contradictions, and regards science 

 and religion as complementary but independent ex- 

 pressions of that unity. M. Boutroux points out here 

 a dilemma; if the activity is indeterminate it is with- 

 out meaning ; if it is concrete it returns to us the - 

 problem with which we started. Finally, the hypo 

 thesis of James that religious experience belongs to 

 the subconscious realm is discussed ; the objection is 

 made that the subconscious must be mediated by the 

 conscious, and that hence its import will again he 





