534 



SCIENTIFIC NEWS. 



[Nov. 23, 1888. 



tion of true and actual teeth. It is, in fact, little or 

 nothing more than a mass of long hairs agglutinated 

 together into a series of plates, some broader and some 

 narrower, fringed at their tips, and set closely side by 

 side. And equally convincing testimony in favour of 

 the argument that it is in no sense a modification of the 

 teeth we find in the fact that it springs, not from the 

 gums or the jaw-bones, but from a layer of vascular 

 substance lying upon the former. And, if still further 

 proof than this be required, it may be found in the 

 presence, in certain whales, of whalebone and true 

 tooth-germs together, although these latter are very 

 small and rudimentary, and never project beyond the 

 gums. The mere fact that they are there, however, tells 

 its own story, and effectually disposes of the theory that 

 the whalebone represents them, although in a singularly 

 modified form. 



In other words, this whalebone, or " baleen," to be- 

 stow upon it the title employed by those instrumental in 

 procuring it, is a special apparatus provided for a special 

 purpose, and not a mere modification of organs which, 

 in all other animals possessing them, are of a widely 

 different character. Yet no account of the teeth of 

 whales would be at all complete without a description 

 of this most curious substance. Although not structur- 

 ally analogous to teeth, and fulfilling none of the ordin- 

 ary duties of teeth, it yet takes the place of teeth, and 

 performs a most important duty which no true tooth- 

 apparatus could satisfactorily fulfil. And this duty, as 

 already stated, lies in the capture of prey. 



Now, strange as it may seem, and indeed almost in- 

 credible, it is nevertheless a fact that the mysticete 

 whales, although numbering among them some of the 

 very largest of all created beings, find their food, 

 and the whole of their food, in the very smallest. They 

 are living exemplifications of the proverb that "extremes 

 meet." And there is a common saying among sailors, 

 and a saying which is strictly and absolutely true, to the 

 effect that a whale sufficiently large to float a jolly-boat 

 in its mouth would yet be choked by a herring. For the 

 gullet of a fully-grown Greenland whale, an animal 

 eighty or ninety feet or so in length, is little more than two 

 inches in diameter ! The animal, therefore, which is 

 strictly predacious, must perforce content itself with 

 victims of minute dimensions ; and these it finds in the 

 form of certain small marine creatures, such as shrimps, 

 medusae, and the young of crabs and lobsters, which herd 

 together in enormous shoals, consisting, very often, of 

 many millions of individuals. Now were its mouth of 

 ordinary character the whale would have, and could 

 have, but little success in the chase. One can scarcely 

 imagine a shark or a walrus pursuing such victims, and 

 making a satisfactory meal upon them. But the posses- 

 sion of the whalebone plates enables the whale to do so 

 without difficulty. All that it need do is to open its 

 mouth to the fullest extent, drive at full speed through 

 the shoal, and enclose a vast number of the tiny creatures. 

 Then the mouth is partially closed, and the whalebone 

 forms a close network around its margins, through the 

 interstices of which the water is ejected, while the little 

 prisoners are retained. As soon as the water is expelled 

 the captives are gradually swallowed, and then the 

 process is repeated again and again until hunger is fully 

 satisfied. 



The amount of this whalebone, and the length of the 

 plates, of course varies very much in accordance both 

 with the species and with the size of the individual 



specimen. In a very large whale indeed some of the 

 plates, of which there are about three hundred upon 

 either side of the mouth, may be twelve feet or more in 

 length, and their total weight upwards of two tons. But 

 whales such as this, in these days of persecution, are 

 exceedingly rare, and half that amount is a very fair 

 quantity to be taken from the fhouth of a single speci- 

 men ; more especially as, so lately as 1884, the best 

 whalebone sold at the rate of ,£2,500 per ton. But this 

 is a somewhat exceptional price, and from £600 to 

 £800 may be quoted as the ordinary rate. 



Whalebone of the first quality is only to be procured 

 from one species of whale, viz., the Greenland, or Right 

 Whale ; but many other whales possess it. Thus it is 

 present in the Rorqual, that giant of his race, but seldom 

 attains to a length of more than four feet ; as there are 

 some eight hundred plates, however, it is still of some 

 little value. It is also found in the Hump-backed, or 

 Bunched Whales, but is generally brittle, and of little 

 service for commercial purposes. And the Pike Whale, 

 Biscay Whale, Japan Whale, and many others possess it, 

 although neither in quantity nor quality sufficient to render 

 their capture desirable. 



The true teeth of the whales we must leave for a sub- 

 sequent paper. 



THE PINEAL OR PARIETAL EYE. 



IN a recent number of the Scientific News, whils' 

 giving an account of the Pelosanrus laticeps, we 

 mentioned, amongst the other remarkable features of 

 this extinct reptile, that it shows evidence of having pos- 

 sessed an eye in the middle of the skull, between the two 

 parietal bones. The existence of such eyes in a variety 

 of vertebrate animals has been exhaustively studied by 

 Professor Baldwin Spencer, who made known his re- 

 markable results in a lecture delivered at Sydney during 

 the late meeting of the Australasian Association for the 

 Advancement of Science. Of this lecture we are able to 

 lay before our readers only a meagre outline, as it is not 

 reported in detail in the Sydney papers, and as the pro- 

 ceedings of the Association have not yet been printed. 

 Professor Spencer said that in the brains of the verte- 

 brate animals there exists a small special part known as 

 the " pineal gland." The meaning of this part has been 

 a problem. Among the suggestions propounded one of the 

 wildest was that it must be the seat of the soul. But it 

 is now ascertained to be the rudiment, or we had better 

 say the remnant, of an eye. This part is much better 

 developed in some species than in others. It varies in 

 structure in mammals, birds, and amphibians, in which it 

 is not very highly developed. In lizards and certain 

 fishes it has become transformed into an eye, the pineal 

 or parietal eye. 



Professor Spencer explained the gradual development 

 of the eyes in lizards, and the ultimate production of two 

 lateral eyes and one intermediate eye. He then de- 

 scribed the structure of the pineal eye in various 

 lizards, especially in Hattcria (the tuatera of New 

 Zealand), Varanus, and Chameleo. The extinct reptiles 

 and amphibians possessed the pineal eye, the use of which 

 has been lost by their descendants, so that in species 

 which now exist this third eye has become a mere rudi- 

 ment, and as far as we can detect, it does not exert any 

 function. 



But a very curious phase of the subject yet remains. 

 It would seem as if this eye had been met with in 



