HARDWICK'E'S SCIENCE-GOSSIP. 



35 



which equally with the other spores, conidia, repro- 

 duce the parent plant when placed in suitable cir- 

 cumstances. 



These two kinds of spores were formerly consi- 

 dered to belong to two different species of fungi, 

 Aspergillus glaucus and Eurotium herbariorum ; 

 they are now known to be the product of one and 

 the same species, which is called Eurotium Aspergil- 

 lus glaucus. 



Many instances of pleomorphism connected 

 with cryptogamous vegetation might be given, 

 differing from this only in certain details, which, 

 although very important, are too minute to be 

 entered upon here ; but I must not refer at pre- 

 sent to more than one other, which has been 

 brought to light of late years by the researches 

 of De Bary, and one which, looking to the fact that 

 it sweeps away all barriers that were supposed to 

 divide the animal from the vegetable kingdom, is 

 so startling in its consequences, that if it rested 

 upon any less authority than that of De Bary, would 

 be supposed to be a mistake of observation. When 

 the spores of certain fungoidal organisms, which De 

 Bary calls Myxomycetes, are placed in circumstances 

 favourable to their germiuation, they burst, and the 

 protoplasm with which they are filled slowly escapes. 

 At first the escaped protoplasm has a globular 

 shape, but presently its circumference begins to 

 undulate, throwing out and withdrawing pointed 

 processes, till it soon assumes the shape of an elon- 

 gated body endowed with motion, and which is 

 provided with a vibratile cilium on the end, that 

 points iu the direction of its motion. Towards the 

 hinder end are to be seen one to three vacuoli, one 

 of which, at least, is contractile, that is, it expands, 

 and again contracts to almost total disappearance. 

 Suspended in water, these bodies exhibit all manner 

 of contractions and extensions of their own sub- 

 stance, while at the same time they exhibit two 

 kinds of motion, one of rotation, the other of pro- 

 gression. At this stage they are not inclosed in any 

 distinct envelope, and, in short, they exhibit every 

 character by which the organisms of the admittedly 

 animal family Amcebae are distinguished, so that 

 there is no good ground for denying that at this 

 period of their life they are as much animals as 

 amoebae are. 



The most remarkable cases of pleomorphism of 

 which I know anything have, however, been brought 

 to light chiefly by the investigations of Mr. Darwin 

 upon certain flowering plants, which he calls dimorphic 

 and trimorphic. In his own words,* "Dimorphic spe- 

 cies consist of two forms, which naturally exist in 

 about equal numbers ; in the long-styled form, the 

 pistil is always longer, and the stamens (excepting 

 in the case of Linum grandiflorum) are shorter, than 

 in the other form. Conversely, in the short-styled 



* Journal of Linn. Soc, Botany, vol. x. p. 393. 



1 form the pistil is shorter and the stamens longer, 

 than in the long-styled form. In the latter the 

 pollen-grains are almost always of larger size than 

 in the short-styled form. The sexual union of the 

 Wo distinct forms is necessary for full fertility. . . 

 When long-styled or short-styled plants are impreg- 

 nated with their own-form pollen, thii union is not 

 fully fertile, or is even absolutely barren. Such 

 unions, and the offspring raised from them, may be 

 called illegitimate. Thus, two legitimate and two 

 illegitimate unions can be effected. 



" With Trimorphic species the case is more com- 

 plex. There are ttiree forms which differ greatly in 

 the length of the pistil ; and in each form two sets 

 of stamens exist, differing in length, in the size of 

 the pollen-grains, and often in colour. The stamens 

 are graduated in length, so that one of the two sets 

 in two of the forms is equal in length to the pistil 

 in the third form. For instance, in the long-styled 

 form the pistil equals in length the longer set of 

 stamens in the mid-styled and short-styled forms. 

 In all three forms the union is fully fertile and legi- 

 timate only when the pistil is impregnated with 

 pollen from the stamens which equal it in length. 

 Thus the long-styled form can be legitimately ferti. 

 lized only by the longer stamens of the mid-styled 

 or short-styled form ; it can be illegitimately ferti- 

 lized by its own two sets of stamens, and by the 

 shorter stamens of both the mid-styled and short, 

 styled forms, so that the long-styled form can be 

 fertilized legitimately in two ways, and illegitimately 

 in four ways. The same holds good with the mid- 

 styled and short-styled forms; hence, with trimor- 

 phic species eighteen unions are possible, of which 

 six are legitimate, and produce legitimate offspring, 

 and twelve are illegitimate, and produce illegitimate 

 offspring." 



It is unnecessary here to multiply instances of 

 the analogy which I suggest exists between the 

 behaviour of living matter and that of non-living 

 matter in respect to pleomorphism, the variability 

 of bodies without loss of identity, for to each of us 

 will occur other illustrations furnished by chemistry 

 or by biology, according to our familiarity with one 

 or other of these sciences. 



REMARKS ON THE ACTINOPHRYS 

 EICEHOBNII. 



THE May number of Science-Gossip, 1875 

 contains some observations on Actinophrys 

 Sol, which I intended to follow up with some further 

 remarks on its economy. But so complicated and 

 numerous were the changes through which they pass 

 in the course of their life, that at present it is 

 impossible to detail or follow out in a satisfactory 

 manner their life-history. The following observa- 

 tions are upon the economy of Actinophrys Eichhomii 



