3CO 



NATURE 



\July 24, 1879 



therefore they cannot represent the fillings of cylindrical 

 tubes in another material. In no sections, neither in 

 those which cut through them at right angles, nor in 

 others which exhibit them obliquely, nor in those which 

 are parallel to their axis, any traces of an intermediary 

 substance separating the single fibres can be found. 

 Also in polarised light the fibre bands appear altogether 

 homogeneous and consisting only oi one kind of material. 

 The pore-canals penetrate the chamber-walls of the 

 foraminifera in such a direction that to the sarcode fila- 

 ments, which, as pseudopodia are sent forth from the 

 chambers into the water outside, they offer the shortest 

 possible way (Figs. 12 and 13). Thus as a rule they lie 

 at right angles to the inner and outer surfaces of their 



Fig. 19. 



chamber-wall, as long as this continues to get uniformly 

 thicker by the deposition of regular layers. If the thick- 

 ening of the chamber-walls takes place in an irregular 

 manner, then it often happens that the pore-canals are 

 curved ; yet even in this case the tendency of the sarcode 

 to reach the outside water through the new thickening 

 layers of its chamber-wall by the shortest possible way 

 becomes apparent. This law is manifest even with the 

 simplest forms of foraminifera, the chambers of which 

 are not even of regular shape and arrangement. Fig. 16 

 illustrates this ; it represents a section of Carpenteria 

 rhaphidodcndron magnified 120 times ; K K are chambers, 

 P P pore-canals. 

 In the direction of the Eozoon fibres, which are supposed 



to correspond to the pore-canals of foraminifera, a similar 

 organic regularity is altogether missing. It is true that 

 in many places they radiate from the surface of the ser- 

 pentine patches, which are supposed to be the fillings of 

 foraminifera chambers, at right angles towards the lime- 

 stone ; yet the direction of the fibres in these places 

 cannot be said to represent the direction of the sarcode 

 of a foraminifera species, because in adjacent parts the 

 direction of the fibres does not always obey the same law, 

 and because for great distances in the fibre bands all the 

 fibres retain a parallel direction, no matter whether they 

 lie at right angles, obliquely, or even tangentially to the 

 serpentine patches. This is shown in Fig. 17, repre- 

 senting a section of Eozoon magnified ninety times ; in 

 the centre is a serpentine patch, S, surrounded almost on 

 all sides by parallel chrysotile prisms ; above to the right 

 there is a smaller patch of serpentine, surrounded by 

 chrysotile fibres of the same direction. The pseudopodia 

 of a living sarcode mass, which once took the place of the 

 serpentine, cannot therefore have determined the direc- 

 tion of the fibres; on the contrary, their parallelism points 

 to an inorganic origin, because it is independent of the 

 curvatures of the boundaries between serpentine and 

 limestone. 



3. The stems in the limestone of the Eozoon are sup- 

 posed to be the siliceous fillings of ramified canals in the 

 intermediary matter of the Eozoon shell. In good sections 

 the stems generally look brownish in transmitted light ; 

 whitish or colourless ones are much less frequent. Their 

 shape, size, direction, and quantity vary extremely, not 

 only when different sections are compared, but very often 

 already in different parts of the same section, even if this 

 measures only a few millimetres in length and breadth. 

 The stems may lie so close together that the spaces inter- 

 vening are hardly larger than their own diameters (Fig. 

 18) ; often they are separated by wide intervals (Figs. S 

 and 18). Sometimes they run parallel (Fig. 18), at other 

 times they radiate from one or more points, or assume 

 the shape of feathers (Fig. 19). They touch the boun- 

 daries of the limestone or are imbedded in the midst of 

 this (Figs. 5 and 18); they are simple (Figs. 18 and 19) 

 or ramified (Figs. 5, 9, 10, and 18), long and slender or 

 short and broad. They terminate in fine points or in the 

 shapes of clubs or spoons. They are straight, bent into 

 knee shapes, curved like waves, or folded and twisted 

 irregularly. 



Their sections generally have sharp edges; round or 

 eUiptical sections, like those of the ramified canals of 

 foraminifera, are rare amongst them. The sizes and 

 shapes of successive sections of one and the same stem 

 may also vary considerably. 



Prof. Moebius concludes his treatise with the following 

 characteristic sentences : — " My task was to examine 

 Eozoon from a biological point of view. I commenced it 

 with the expectation that I should succeed in establishing 

 its organic origin beyond all doubt. But facts led me to 

 the contrary. When I saw the first beautiful stem-systems 

 in Prof Carpenter's sections, I became at once a partisan 

 of the view of Professors Dawson and Carpenter ; but 

 the more good sections and isolated stems I examined, 

 the more doubtful became to my mind the organic origin 

 of Eozoon, until at last the most magnificent 'canal- 

 systems ' taken all together and closely compared with 

 foraminifera sections preached to me nothing but the 

 inorganic character of Eozoon over and over again. 



" In the minds of other zoologists, while showing them 

 a series of my finest Eozoon sections, stem preparations, 

 and foraminifera sections under the microscope, I have 

 repeatedly in the course of an hour called forth these 

 mental metamorphoses, which I passed through in the 

 course of a long period of investigation. 



" I am heartily sorry that, by way of thanks for the 

 extremely kind support which Professors Dawson and 

 Carpenter have given me in these investigations by 



