November 26, 1914J 



NATURE 



339 



of air, or electric shocks; or it may occur 

 spontaneously. There is great specific and in- 

 dividual diversity in susceptibility ; the easier the 

 inducing- of the hypnosis, the deeper and more 

 lasting it is. The muscular tonus changes charac- 

 teristically (now great stiffness and again "waxy 

 flexibility ") ; resistance to fatigue is increased. 

 Reflexes are to some extent affected by the altered 

 tonus. Sensitiveness to touch and to pain may 

 be greatly lessened, and operations ma}* be per- 

 formed during hypnosis. But the senses remain 

 awake, and, except in the deeper phases in man, 

 memory partly persists. Anaemic symptoms are 

 sometimes observed, but there is no regular altera- 

 tion in the everyday functions, such as the beating 

 of the heart or the respiratory movements. Since 

 animal and human hypnoses agree in all these 

 respects. Mangold has confidence in his thesis that 

 they are thoroughly analogous phenomena. 



Finally, in his interesting study, he proposes a 

 classification : — 



1. Experimental hypnosis induced by psychical 

 inhibition (suggestion hypothesis) : (a) in man, and 

 (b ) perhaps in some of the highest mammals ; 



2. Experimental hypnosis induced by mech- 

 anical inhibition : (c) in mammals, birds, reptiles, 

 and amphibians, and (d) in crustaceans and 

 insects ; 



3. Natural hypnosis induced by " biological " 

 stimuli : [e) death-feigning in crustaceans and 

 insects, and (/) katalepsy in stick-insects. 



DEEP SEA EXPLORATION A 



TN their book entitled "The Depths of the 

 -*- Ocean," which was noticed in Nature of 

 October 24, 1912, the late Sir John Murray and Dr. 

 Hjort gave a general account of the expedition 

 of the Michael Sars in the North Atlantic, and 

 discussed the most striking results which had 

 been obtained. The material collected had, how- 

 ever, been only partially worked out when that 

 book was published. The more detailed scien- 

 tific reports are now to be issued in a series of 

 volumes containing memoirs by different special- 

 ists. The present volume is the first of these 

 reports to be published, and deals with some of 

 the zoological results of the expedition. 



The Cephalopoda are described by Prof. C. 

 Chun. A large number of species were obtained, 

 several of which are described as new, but 

 perhaps the most interesting feature of the collec- 

 tion is the series of early stages of Spirula aus- 

 tralis, Lamarck. These were obtained in the 

 neighbourhood of the Canary Islands, where they 

 were taken in plankton nets. There were three 

 larval stages, of which the youngest is 6 mm. 

 long and has five chambers projecting at the 

 posterior end of the body ; the next has six visible 

 chambers, and the third is 9 mm. long with seven 

 chambers. In addition to these larvae, young 

 stages with dorsal mantle lengths of 12 mm., 



1 Report on the Scientific Results of the Michael Sars North Atlantic 

 Oeep-iea Expedition, igio, carried out under the Auspices of the Norweeian 

 novernm<'nt and the Superintendence of Sir John Murrav, K.C.B., and Dr. 

 Tohan Hjort. Vol. iiL, part i. Zoology. (Published by the Trustees of the 

 Bergen Museum.) 



NO. 2352, VOL. 94] 



lO mm., 18 mm., 23 mm., and 26 mm. respec- 

 tively were obtained. Excellent figures of the ex- 

 ternal appearance of these larvae and young stages 

 are given. ITieir internal anatomy has not, 

 however, yet been examined. The memoir ends, 

 to use Prof. Chun's own words, "with the de- 

 scription of a new and wonderful type of Cirroteu- 

 thida, which may probably be counted among 

 the most valuable spoils of the expedition. The 

 specimen is a perfectly gelatinous, semi-trans- 

 parent cephalopod, the fragility of which recalls 

 that of a ctenophore. " To this interesting animal, 

 which is fuly described and well-figured, the name 

 of Cirrothauma Murrayi, n. gen. and n. sp. is 

 given. 



The Cirripedes are described by the late Dr. 

 P. P. C. Hoek, the forms obtained being all previ- 

 ously known, and Dr. Kr. Bonnevie deals with the 

 Pteropods. Dr. Bonnevie 's memoir contains an 

 elaborate and useful discussion of the two species 

 Linuicina balea and L. retroversa, about which 

 very great confusion has existed. Dr. Bonnevie 

 shows clearly that the two forms are distinct, 

 and he describes the limits of variation in certain 

 characters of the shell of each species. 



The Scyphomedusae, Pennatulacea, and Hy- 

 droida are treated in three memoirs by Dr. 

 Hjalmar Broch. It is to be regretted that Dr. 

 Broch commences his first paper b\- an unfortun- 

 ately worded attack upon the scheme of plankton 

 nomenclature which was introduced a good many 

 years ago by Dr. G. H. Fowler. The "epi- 

 plankton " of Fowler is certainly not the same as 

 the " meroplankton " of Haeckel, as Dr. Broch 

 seems to think, but is that part of the "holo- 

 plankton " which lives between the surface and 

 100 fathoms. This is clearly explained in 

 Steuer's " Planktonkunde " (p. 370), to which 

 work Dr. Broch refers for support. Steuer him- 

 self would seem to have adopted Apstein's term 

 "passiv limnetische Planktonten," for the forms 

 in fresh water which attach themselves to other 

 organisms, remarking that these forms have been 

 called " epiplanktonic. " In one instance (p. 616) 

 only, so far as his index shows, he uses the term 

 in the latter sense without qualification, and he 

 nowhere gives any indication as to when or by 

 whom it was first introduced. If it is shown that 

 the word " epiplankton " had been employed in 

 another sense previous to its use by Fowler, then 

 it may be necessary to find a new term for what 

 Fowler calls "epiplankton." 



In the Michael Sars collections Dr. Broch finds 

 ten species of Scyphomedusae, of which two, 

 Nausithoe atlantica and N. globifera, appear to 

 be new, five species of Pennatulida and a con- 

 siderable number of hydroids obtained partlv from 

 drifting sea-weed and partly from hauls of the 

 young-fish trawl. An interesting figure, drawn 

 by the artist on the Michael Sars, 'is given, in 

 which an attempt has been made to represent the 

 appearance of the Pennatulid Umhellula gi'iutheri 

 when in a state of phosphorescence. 



The Muraenoid Lar^'se, which formed a most 

 important collection, are described by Einar Lea. 

 The general results as regards the occurrence of 



