On the eyes, the integumentary sense papillae, and the integument of the San Diego blind fish (Typhlogobius Californiensis, Steindachner) / by W. E. Ritter.

  • William Emerson Ritter
Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: On the eyes, the integumentary sense papillae, and the integument of the San Diego blind fish (Typhlogobius Californiensis, Steindachner) / by W. E. Ritter. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    developed on the head and sides of the body of both Amblyopsis and Typhlichthys. According to Packard ('86, p. 127), Tellkampf regarded these papillae as without doubt increasing the tactile sense. I have not seen this paper of Tellkampf's, and do not know whether his mean- ing would be that the tactile sense is increased as compared with what it was in the same species before it was deprived of sight, or merely that it is great as compared with other bony fishes. Leydig also be- lieves that the tactile organs perform such a compensatory office ('83; see also Wright, '84, p. 272). Packard ('86, pp. 127, 128) gives ex- tracts from several letters of Dr. John Sloan that are interesting in this connection. Although the writer does not expressly state his belief that the sense of touch has been highly developed for the purpose of compensating the lack of sight, he still gives very convincing evidence of its extreme acuteness from personal observation on the fishes in their native surroundings. It should also be noticed that he specially tested their powers of hearing and the effect of light upon them, and to both he says they manifested total indifference. Sloan's observations were on Amblyopsis. Wyman ('72, p. 19) has described the ear of this spe- cies as being largely developed in all its parts, and Cope ('72, p. 410) found the sense of hearing evidently very acute. As to the ques- tion whether the sense papillae in Amblyopsis and Typhlichthys are in reality developed as a compensation for the loss of sight, the testimony furnished by Chologaster is of the greatest importance. Although this genus was discovered and named by L. Agassiz in 1843, its characters were best made known by Putnam. He ('72, pp. 22, 23) says : In the genus Chologaster we have all the family characters as well expressed as in the blind species, though it differs from Amblyopsis and Typhlich- thys by the presence of eyes, and the absence of papillary ridges on the head and body, and by the longer intestine and double the number of pyloric appendages, as well as by the position of the ovary. In 1881, S. A. Forbes ('82, p. 3) discovered a fish in Southern Illinois which he identified as belonging to the genus Chologaster, but repre- seutiug a new species. With reference to the point that we are now considering, the author writes: The most important and interesting peculiarity of this species indicates a more advanced stage of adap- tation to a subterranean life than that of its congeners. On all the surfaces of the head appear short rows of peculiar tubercles. . . . When thus exposed [by being freed from the adjacent epidermis], they closely resemble the papillae of Amblyopsis in form and size, and are similarly cupped at the tip. Again (p. 5) he says: The extraor-
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