April 25, 1895J 



NA TURE 



60' 



ontent ourselves with a collection of rules and portents, 

 jie belief in which we fondly thought the Education Act 

 (ind the School Board had utterly abolished. I 



' And even here our old friends, when brought out for ] 

 JUT edification, are not in the form in which they are I 

 !amiliar,and have been long beloved. Look at the bald- 

 less of the assertion — " Expect bad weather if cats wash 

 heir faces and lick their bodies." Contrast it with the 

 najestic roll of the well known couplet — 



Puss on the hearth, with velvet paws, 

 Sils, wiping o'er her whiskered jaws. 



We distinctly feel that we are robbed of something; 

 :here is such a pleasant jingle in the old rhyme, that it 

 :arried conviction with it. How disappointing, too, to 

 De told o nly to expect. We may just mention, in passing, 

 that this is not the conclusion which we should expect 

 Ithe average fourth standard boy to draw from witnessing 

 Ithe operation on the part of " puss." We should expect 

 that young gentleman to remark that " cat's hair appeared 

 to be slightly hygroscopic" 



Altogether this little book reminds us of those admir- 

 able compilations in which the theory of whist is .,ome- 

 times exposed : a vast number of rules is given, which if 

 one could remember and select at the right time he 

 would never make a mistake ; but, unfortunately, the com- 

 binations on which the rules are founded have a knack of 

 I eluding the unlucky player, and never seem applicable to 

 the hand in play, with the consequence that in his etForts 

 to remember some rule, he trumps a thirteenth at an 

 inopportune moment, and earns the contempt of a long- 

 suffering partner. In the same manner one can conceive 

 the city man, armed with this collection of precious and 

 invaluable rules for determining the weather of the 

 coming day, debating with himself whether it was last 

 night or this morning that the sky was red ; did he, while 

 shaving, see his dog eating grass on the lawn ; and what 

 is the exact age of the moon — finally getting confused by 

 the knowledge that the train is nearly due, rashly seizing 

 his mackintosh and umbrella in the middle of a well- 

 determined summer anticyclone, and so forfeiting his 

 hard-earned position of a trustworthy weather prophet 

 and a man of keenness and nicety of observation. 



THE MYCETOZOA. 

 A Monograph of the Mycetozoa; being a Descriptive 

 Catalogue of the Species in the British Museum. 

 Illustrated with seventy-eight plates and fifty-one 

 woodcuts. By Arthur Lister. (Printed by order of 

 the Trustees. London : 1894.) 



ALTHOUGH this is an official publication of the 

 Natural History Department of the British Museum, 

 that part of the title referring thereto is somewhat mis- 

 i leading, because the author includes everything published 

 1 belonging to this curious group of organisms, .-^t the 

 I same time it is not a monograph in the strict sense of the 

 I word, because the author had no opportunity of examining 

 I a laige number of the reputed species inhabiting Central 

 Europe, Scandinavia and North .-Vmerica. Thus, out of 

 15 species of Badhamia, only 9 came under his observa- 

 I tion ; of Physarurr., 30 out of 45 ; of Didymium, 8 out 

 of 17, and so on all through. It is true that he repeats, 

 NO. 1330, VOL. 51] 



in English, the authors' descriptions, and frequently 

 suggests the affinities of the species in question. 



Further, apart from the fact that the book was pub- 

 lished under the authority of the Tnistees of the British 

 Museum, and the fact that " ever)- species of which I 

 have given the characters can be examined either in 

 bulk, or as a mounted object in the British Museum," 

 it might with equal propriety have been entitled a 

 descriptive catalogue of Mr. Lister's own herbarium, or of 

 the Kew herbarium, because, as he acknowledges, he had 

 full use of the Kew set, including all Berkeley's numerous 

 types. 



However, this does not aSect the character and quality 

 of the work. Mr. Listers previous contributions to the 

 literature of these curious and debatable organisms were 

 a sufficient guarantee of good and really original work, 

 and he has no doubt met all reasonable expectations on 

 this point, Indeed few works have recently been issued 

 embodying so much original research. The ^fycetozca, 

 as limited by De Bary, Rostafinski, Lister, and others, are 

 essentially the same as the Myxogastres of Fries and the 

 Myxomycetes of Wallroth. The first name was substi- 

 tuted for the older ones because it was discovered that 

 the spores, instead of producing a mycelium as in fungi, 

 gave birth to swarm-cells which coalesce to form a 

 Plasmodium ; thus indicating a relationship with the 

 lower forms of animal life. Mr. Lister adopts this 

 designation, and defines the group as follows : — 



" A spore pro\ided with a firm wall produces on germin- 

 ation an amceboid swarm-cell which soon acquires a 

 flagellum. The sv<-arm-cells multiply by division and 

 subsequently coalesce to form a Plasmodium which 

 exhibits a rhythmic streaming. The plasmodium gives 

 rise to fruits which consist of supporting structures 

 and spores ; in the Endosporea, these have the form 

 of sporangia, each having a wall within which the free 

 spores are de%'eloped. .A. capillitium or system of 

 threads forming a scaffolding among the spores is 

 present in most genera. In the Exosporea the fruits 

 consist of sporophores bearing numerous spores on 

 their surface." 



He then proceeds to describe in detail the develop- 

 ment aud various stages, in fact the life history of these 

 organisms, and this he has done in a simple and lucid style 

 worthy of all admiration. The movemsnts of the swarm- 

 cells — creeping and dancing movements — are most inter- 

 esting, as well as that of the plasmodium, or ag^egation 

 of cells ; but the feeding of the swarm-cells is most 

 exciting. Mr. Lister had pre\-iously published accounts 

 of his o bsen-ations of the ingestion of food-material by 

 the Mycetozoa in this stage of their development ; yet a 

 sh rt extract relating to this process is not out of 

 place : — 



" If baaeria are introduced into a cultivation of 

 swarm-cells on the stage of the microscope, they are seen 

 to be laid hold of by the pseudopodia and drawn into 

 the body of the swarm-cells, where they are enclosed in 

 a digestive vacuole. Several bacteria are bnught in 

 turn to the same chamber, or fresh captures are conveyed 

 into one or more additional vacuoles. The protrusion 

 of pseudopodia usually ceases after such ingestion, and 

 that part of the swarm-cells takes a rounded form. In 

 the course of an hour or two the bacteria are assimilated 

 and the digestive vacuoles disappear. Unicellular algae 

 and inorganic matter are sometimes taken in, which after 

 a time are again discharged. Both ingress and egress 

 are observed to take place only at the posterior end." 



