28 LAND AND FEESHAVATER 



Benson, in the A. M. N. H., Aug. 1850, p. 92, first described the 

 animal : — " The examination of living specimens of Otopoma dausura 

 8ow., from Kattiawar, enables me to contrast the animal of that 

 shell with Hjihocystis. In 0. clausum the foot is moderate in length 

 and composed of two long, narrow, parallel soles, separated by a 

 deep sulcus, and having also a deep sinus between them at either 

 end. The muzzle is greatly elongated, emarginatc in front, and the 

 lateral lobes are capable of considerable extension. The tentacula 

 are moderate, hyaline, ringed, tumid and obtuse at the extremity. 

 The eyes are prominent on the outer side of the tentacula near their 

 base, not sessile on the head. On communicating to Mr. Theobald 

 a remark on the peculiar sole of this animal, he stated that he had 

 noticed it, and tliat its use was to enable the species to cling to the 

 thin stems of the branches of the shrub which it frequented near 

 the shore of Gopnath Point, on the Gulf of Cambay. The leaves 

 which he forwarded were kindly examined for me by Sir W. J. 

 Hooker, and were pronounced to be those of Grewia betulifolia, 

 DeCand., an inhabitant also of Arabia, whence Sowerby's* type 

 specimens of 0. clausum were procured." 



These remarks really refer to a distinct species and noted as such 

 by Mr. \V. T. Blanford in A. M. N. H. xiii. p. 404 (1864), as Otopoma 

 Jiindiiorum, and described fully in J. A. S. E. 1870, pi. iii. fig. G, 

 p. 12. 



The shell is figured also in the Conch. Indica, pi. vi. fig. 5, and a 

 variety, with no locality given, fig. 0. Blanford remarks, J. A. S. B. 

 1870, p. I'd: "From Cydostoma {Otopoma) dausuiu. Sow., to which 

 Mr. Benson referred the present form, it is distinguished by being 

 smoother, and with a less excavated umbilical region and a higher spire. 



" I have not previously published a complete description or figure 

 of this shell. It is the most eastern form of the subgenus known, 

 other forms assigned to Otopowa found in the Indian and Burmese 

 areas having been shown to belong to the Cyclophoridae." 



It is interesting to note that the habits of this operculated form 

 follow so closely those of the BuUmi of dry desert countries like 

 Arabia and Socotra, &c. These latter are to be seen in closely 

 packed masses on the stems of plants, the peristome firmly glued 

 down to the surface of the plant-stalk. 



The divided foot may possibly assist a small species like Otopoma 

 Jdiiduoram in its ascent of plants, but it cannot be said that this 

 structure of the foot has any direct connection with a climbing 

 habit or was brought about by such a habit. The character is one 

 common to the CyclostomidiB, and its physiological interpretation 

 and original development have yet to be sought for, and must be of 

 very remote evolutional origin. 



Professor Bayley Balfour, the distinguished botanist, on his well- 

 carried-out expedition to Socotra in 1880, brought back with him. 

 among the very interesting collection of shells he then made, and 

 which were recorded in the P. Z. S., Feb. 1st, 1881, some well- 

 preserved spirit-specimens of Otopoma. 1 am thus enabled to 

 give some details of the anatomy, and add them to the generic 

 description of the genus. 



