56 



HA RD WICKE'S SCIENCE- G OS SI P. 



A dog will hear distant sounds, and prick up his 

 ears at the rolling of carriage-wheels, unperceived by 

 us, but musical harmonies are wasted on him, or 

 even disliked, and a new chord struck, or the song 

 of a bird, is apparently unrecognised. 



Again it is quantity versus quality. And if we are 

 driven to defend the down on the human body, and 

 even the os coccyx, we shall find the same argument 

 to hold good. As a matter of fact, the fur of lower 

 animals corresponds strangely to the rudimentary 

 condition of our own liner covering. In a very early 

 stage of man's formation, " the whole surface " of the 

 body is "thickly clothed" with " wool- like hair," 

 which Mr. Darwin himself recognises as "probably 

 representing the first permanent coat of hair in those 

 mammals which are born hairy." 



What authority, then, has your correspondent for 

 stating that the "down covering a man's body is 

 certainly in a more rudimentary condition as regards 

 the hair on lower animals " ? Precisely the same 

 may be said with regard to the os coccyx, which is 

 known to project in an early stage. 



Again, the tail is the rudimentary condition of the 

 more perfect shortened formation, and corresponds to 

 the appendage in lower animals. 



While we are taught so carefully to trace in man's 

 own individual development the picture of the great 

 scheme of evolution — from the lowest of vertebrata to 

 man, the highest — it is curious that this simple 

 conclusion should have been overlooked. Are we 

 still to term organs rudimentary, though we know 

 that to increase them to dimensions of the lower 

 animals would be to return to our own embryological 

 condition, from which they had scarcely emerged? 



The brain of an adult baboon, Mr. Darwin tells us, 

 corresponds in development to the human brain in its 

 early rudimentary condition. With these facts before 

 us, we may surely infer that the ape represents to us 

 a creature fashioned after the likeness of our own 

 rudimentary state, and the same could be said with 

 reference to other low forms. 



Their structures are found to correspond to more 

 or less rudimentary stages in man's individual early 

 existence. If this be indisputable, the word "rudi- 

 mentary " when applied to any part of a fully- 

 developed human organism, is incorrect, and even 

 where traces of a lower condition may be found, 

 they should be regarded merely as an arrest of 

 proper development from its own rudimentaiy con- 

 dition. 



A curious question arises from Mr. Darwin's 

 theory of the process through which organs have 

 passed in becoming rudimentary. He says, "Rudi- 

 mentary organs have been slowly formed through 

 continued disuse, acting by inheritance at a corre- 

 sponding age, aided by the principle of the economy 

 of growth, all under the control of Natural Selec- 

 tion." He explains the modification of an organ to 

 a rudimentary state, through Natural Selection, etc., 



by the same slow processes that were required for 

 its first development. 



But the question is, Where are we to look for the 

 stages of its first progress to development ? If the 

 fur of an ape were down developed to perfection, 

 what is the history of its evolution, and on what 

 ancient animal did rudimentary down first appear ? 

 The answer is as startling as apparent. 



Supposing the simple brain of a savage, through 

 use, inheritance, and Natural Selection, gradually 

 evolves into the fully-developed brain of a civilised 

 being, and then, in course of generations, through 

 disuse, acting by inheritance, gradually loses its 

 powers, the civilised man reverts to the savage. 



Thus, if the down of the ape is found on man 

 in its undeveloped vestigial condition, we must 

 argue that man was originally the progenitor of the 

 ape, and his down the rudiment of the futuie fur. 



I cannot close this article without explaining that 

 arguing on evolution ground only should I use such 

 terms as "excrescences" and " deficiencies " with 

 regard to organs in the lower animals, and I am 

 prepared to defend the position, but my paper has 

 already exceeded in length. To the non-evolutionist 

 every group is perfect in its kind, and for its environ- 

 ment. N. F. L. 



NOTES ON FOSSIL CONCHOLOGY. 



THE subject of these notes, is, I may say, a vast 

 and almost an inexhaustible one, and it is very 

 difficult to know where to begin ; therefore, I propose 

 to deal, in the first place, with the genus Planorbis. 



The Planorbes are freshwater molluscs, and abound 

 principally in still water, although, occasionally found 

 in streams. The animal is elongated, slender, and 

 rolled up ; the head is furnished with two long 

 contractile tentacles, at the internal bases of which 

 eyes are placed ; the orifices are on the left side ; the 

 organs of generation distinct. 



General character. — Shell discoidal ; spire de- 

 pressed ; volutions apparent above and below ; aper- 

 ture lunate, crescent-shaped or sub-quadrate, impinged 

 upon by preceding volution ; outer lip generally 

 thin, sharp-edged, columellar lip spreading over the 

 body whorls. No operculum. All fossil remains of 

 this genus are found in fresh water, or transition 

 formations. 



Pl.ANORBis, Geoffroy. 



Planorbis obtusus, Sowerby. (Fig. 26, 1, a, b.) — 

 This very pretty shell has a smooth, shining, nearly 

 polished surface ; it is depressed, nearly flat on the 

 upperside, and slightly concave beneath. Thevolutions 

 are four or five in number, separated by a deep suture, 

 slightly convex on both sides, but rather more com- 

 pressed on the under side than the upper, obtusely 

 rounded at the periphery, and each nearly half- 



