HARDWICKE'S SCIENCE-GOSSIP. 



of a circle, but the Diatom was not released. Attached 

 to it were two gelatinous masses, one on each side of 

 the frustule similar in size to those described in a 

 former case (in the case to which he alludes he saw the 

 two masses moving steadily along the frustules from 

 one end to the other, making a momentary halt at the 

 centre ; the mass was as large as the width of the 

 Diatom) ; these masses acted in a similar manner in 

 the second case. Furtheron he remarks that he, "from 

 the study of the Diatom shell, has been led to accept 

 the opinion that the raphe is a real fissure in the 

 shell, but in many cases it is not a simple vertical 

 linear opening of the shell. It is more like the over- 

 lapping of the edges of curved tiling in a roof, the 

 thickened line of silica borders one lateral half of the 

 shell, while the other dips under it with a thin film ; 

 this may be easily seen in some of the large 

 Pleurosigmas." 



The cleft which Mr. Corda says he saw at the 

 apex of Pharyngoglossa was possibly a partial separa- 

 tion of the two valves of the frustule. The so-called 

 alimentary canal was the median line, and the aper- 

 tures the central and terminal nodules, the " plug " 

 however does not admit of so easy an explanation. 

 The se.xual conjugation we now know was simply two 

 frustules about dividing. The phenomenon which he 

 relates having seen take place in Siirirella Voiits was 

 no doubt the expulsion of an uuxospore ; and the so- 

 called mantle, the mucus surrounding it. With 

 these few words of explanation we will now allow the 

 author to speak for himself. 



The Habitats of these animalaiks. — An attentive 

 observer cannot approach the sources of the thermal 

 waters of Carlsbad and other thermal waters without 

 remarking, on the wood and stone that border the 

 fountains, a green slimy and gelatinous carpet in more 

 or less dense layers (feuillete). They are seen very 

 developed on the timbers surrounding the Sprudel, on 

 the stones of serpentine that border the Neubrunn, on 

 the water in proximity to the Bernardsbrunn, on the 

 conduits by which the water from the Schlossbrunnen 

 escapes, on the pipes which supply the various bathing 

 establishments, on the rocks, and on the soil of the bed 

 of the Teple, in a word, on every place over which the 

 thermal waters flow. On examining this unctuous and 

 gelatinous mass it is found to conceal myriads of beings 

 elegantly and symmetrically organised, belonging for 

 the greater part to the animal kingdom, and which 

 by their forms, modes of living, and manner of propa- 

 gation cannot fail to excite the most profound astonish- 

 ment. It is in this chaos of slimy matter, and which 

 to appearance is lifeless, we find — the eye being armed 

 with a powerful glass — symmetrical forms more varied 

 and elegant than the most facile painter of arabesques 

 could have imagined. Nevertheless, these myriads 

 of forms are animated, exhibiting under the same 

 type an infinite variety of shapes, whose corpuscules 

 are often not more than the ^-^^ nearer, I say fifteen 

 million parts of a Paris inch ! and rarely exceed j^f^j 



of the same measure ; presenting organs simple if com- 

 pared with animals of a higher order, but equally 

 complicated and admirable in relation to their proper 

 bodies. They move and have sensation for their 

 conservation and propagation, generally possessing 

 the means of assimilating heterogeneous matter, and 

 retaining their vitality for some time when placed in 

 conditions unusual to their nature. 



Warmth, solid matter in the water, and incipient 

 putrefaction, seem to be indispensable to their pro- 

 duction and propagation ; we always find them when 

 these conditions are combined. 



Without moisture they cannot continue to exist ; 

 solid matter and humidity when in contact according 

 to physical laws produce heat, and it is only by the 

 simultaneous action of moisture and heat that 

 putrefaction is possible. When we sometimes meet 

 with these animalcules in the foam of streamlets and 

 rivers, they have not been engendered there, but 

 brought by the current 



To be able to examine these aggregations of 

 animals, we collect by means of a knife the green 

 matter, and place it in a wide-mouthed glass, filled 

 with the water in which they lived, or, in default of 

 that, in water from a river. 



The microscope destined for their examination 

 must show the objects clearly and much magnified. 

 Those ofPisterand Schick of Berlin, Plossl of Vienna, 

 and Chevalier of Paris are the best, and magnify from 

 looo to 3000 times. Those that do not magnify more 

 than 500 or 600 times will not serve for these researches. 

 To examine this green matter we place a small piece 

 about the size of a pin's head on the glass disc of the 

 stage and tear it in pieces with two pointed instruments, 

 or with piris, and moisten the fragments with a drop of 

 water. We now examine it with a power of 100 to 200 

 times, in order to observe their forms more distinctly. 

 Where the animalcule is distinctly recognised, it must 

 be allowed to remain undisturbed under the instru- 

 ment, and then examined again with a power of 400 to 

 600 times. It is only after having become familiarised 

 with its form and habit that we can proceed to those 

 researches we have in view. 



After having acquired by numerous trials a certain 

 dexterity, we proceed to the anatomy of the animal- 

 cule ; this can be done in two ways. The first is very 

 easy and simple : we take a piece of very thin glass 

 (thin as paper) which we place over the animalcule, 

 which will be flattened by its pressure and will 

 remain so during the examination. 



The second requires considerable dexterity, and 

 consists in separating the larger species by means of 

 a very sharp pointed needle, a proceeding requiring 

 a very acute eye, and patience ; perseverance is 

 required in all kinds of investigations, but more 

 particularly so in microscopic observations, which 

 require to be repeated and varied, but this trouble is 

 amply rewarded by the discovery of new and beauti- 

 ful forms of which we have never dreamt, or which 



