Zool. Also -solis. [irreg. f. Gr. τυφλός blind + σωλήν channel, pipe.] A ridge or fold extending along the inner wall of the intestine and partly dividing the cavity of it, in various animals, as lampreys and certain ascidians, mollusks and worms.
1859. Todd’s Cycl. Anat., V. 297/2. In the Earth-worm, there is a singular apparatus, the typhlosole.
1877. Huxley, Anat. Inv. Anim., x. 604. In many Ascidians, a strong fold of the endoderm of the intestine projects into its interior, as in Lamellibranchs and in the Earthworm, where such a fold constitutes the so-called typhlosole.
1881. Darwin, Veg. Mould, 19. The intestine [of the earth-worm] presents a remarkable structure, the typhlosolis.
1888. Rolleston & Jackson, Anim. Life, 435. The mid-gut … in the Lampreys contains a projecting fold or typhlosole.
Hence Typhlosolar a., pertaining to or of the nature of a typhlosole.
1887. Benham, in Q. Jrnl. Microsc. Sci., March, 566. The dorsal trunk divides into two. A subneural vessel is present and a typhlosolar vessel.
