73 ESCHRICHT AND REINHARDT 



the whalebone blades from their pulps, and only in the newborn individual that we were able to 

 obtain a view of the matrix of the entire set of whalebone on either side. On the cranium of the 

 twenty-two feet long skeleton both sides of whalebone were still attached to the palate, even to 

 the whole extent, but they were much too far advanced in decomposition to allow of successful 

 loosening of the horny baleen. It was on both occasions quite evident that the pulp-blades of the 

 whalebone of the Greenland whale, no less than those of the rorquals, are provided with filamentous 

 hair-pulps on their inner and lower edge, only that these soft filaments in conformity with the hairs 

 themselves are a great deal finer both on the free margin and in the interior of the baleen-blades. 

 Besides this, they also appeared to us to be much shorter, in the newborn specimen only six 

 lineSj in the full-grown animal (judging by the foremost and hindmost blades of the whalebone 

 sets) hardly much longer, but it is no doubt extremely probable that the filaments may have been 

 torn by the artificial loosening of the whalebone blades of the full-grown individual as well as by 

 the loosening brought about by putrefaction in the newborn one. 



The result of these observations as to the relation between the horny blades and their pulps in 

 the Greenland whale is this, that though, as might be expected, it is in all essential points similar 

 to that which obtains among the rorquals, yet there are some very remarkable deviations, all cor- 

 responding with the disproportionately finer and more compact inner structure of the whalebone 

 blades of the former. 



We shall now give some observations illustrative of the differences of age in the whalebone 

 of the Greenland whale. 



It seems to be an invariable rule that the whalebone does not appear until about the 

 beginning of the latter half of uterine life. In our eight feet and a half long foetus 

 no traces of it were as yet to be discovered. In its earliest condition we have observed it 

 in the head sent down in brine by Captain HolboU, which was three feet eight inches long, or only 

 four inches shorter than that of the newborn individual. This was most certainly the head of an 

 unborn animal, though as a foetus almost full-grown ; and by comparing it with that of the newborn 

 specimen we may obtain a very clear conception of the state of the baleen at the time of its 

 birth. 



In the foetus the soft " gum" was so disproportionately large that the whalebone blades, though 

 the longest of them had already a length of three inches when measured by their exterior smooth 

 edge, were nevertheless almost totally hidden by it, and only the bristles projected freely. The 

 subsidiary blades were so entirely enveloped in it that they looked like narrow and diminutive 

 stripes, or thick fibres of a white colour, though on a more minute examination they were found 

 to consist each of a fasciculus of hairs agglutinated by the " gum." A special cortical tissue was 

 not yet distinguishable in any of these delicate subsidiary blades, and this might perhaps serve as 

 a sufficient proof that the hairs are the primitive formation of every baleen-blade if this were not 

 evident by the general rule, that in the development of corneous substances the extremity is 

 always the part first formed. The chief blades were already provided with a cortical layer, though 

 only in the shape of a very thin horny covering ; they consisted chiefly of a soft but tough 

 medullary tissue, which could easily be split into horny fibres, all of them perfectly 

 straight. 



With the just-described laminæ of the whalebone of the foetus those of the newborn sucker 

 perfectly agreed, at least as far as we might judge from the chief blades still remaining, and the 

 pulps on the palate of the latter perfectly corresponded with those of the former, not only as to 



