SENSE ORGANS OF AMIURUS. 259 
papillary spaces, varies according to the part of skin where the 
tumour is attached. On the lips, for instance, where there are no 
- clavate cells, the interpapillary spaces are chiefly occupied by spindle- 
shaped cells, but elsewhere, where clavate cells occur, these also are 
proliferated, being found in regular nests such as are represented in 
Fig. 3. Everything indicates rapid division, but no further peculi- 
arity has attracted my attention nor can I furnish any explanation of 
the appearance of these, no doubt, pathological growths. 
CUTANEOUS SENSE ORGANS. 
Within recent years important contributions to the knowledge of 
the sense organs lodged in the skin of Teleosts have appeared. Fol- 
lowing up his earlier researches Leydig’ has recently described those 
of Hsox, Gasterosteus, Acerina and Lota. Solger* has studied the 
organs of the lateral line in various forms, and Bodenstein* has given. 
a careful description of those of Cottus gobio. 
I have not had access to Merkel’s work* in which’ a sharp distinc- 
tion is drawn between two classes of cutaneous sense organs. Those 
which he terms ‘ End-knospen,’ (end-buds), the ‘beaker-shaped 
sense-organs’ of Leydig, are lodged on papille of the cutis, and, 
although freely distributed over the skin and in the mouth cavity of 
Teleosts, are only found in the latter situation in higher vertebrata, 
where they reappear as taste-bulbs. To the second class belong the 
end-organs of the nerves, which are distributed to the lateral line and 
the ‘mucous’ canals of the head. Merkel terms this second class 
‘ Nervenhiigel,’ (nerve-hillocks), and points out their tendency to 
withdraw themselves for protection from the surface of the integu- 
ment within more or less completely closed canals, although, primi- 
tively, all nerve-hillocks are free and exposed to the surrounding 
medium (except for a protecting tube of cuticular origin), and in some 
species such ‘free-organs’ are alone present. The end-buds, on 
the other hand, are always flush with the surface, certain of the ele- 
ments even projecting beyond it, and indeed may be carried beyond 
the general level of the integument where tactile sensibility is at its 
highest development, as in the Kentucky blind-fish (Amblyopsis), 
the Indian Cyprinoids recently described by Leydig, and, in fact, in 
1]. c. p. 22, etseq. 2 Arch.mik. Anat. XVIII., 384. 3% Zeit. wiss. Zool. XXXVII., 121. 
#** Ueber die Endigungen der sensiblen Nerven in der Haut der Wirbelthiere.” 
5» Vide Wiedersheim Lehr. der vergl. Anat. S. 358. 
