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264 or so rapidly as the other parts of the body. In addition to augmented facilities for feeling about in muddy water, they have a considerable development of the auditory organs, which doubtless must be of essential use to them. Their power also of employing the air-vessel as a float appears to be subservient to that of hearing; living as they do a life of groundfeeders, this organ is more serviceably restricted to acoustic purposes. These fishes are almost absent from the clear waters of the Red Sea; they are more numerous in the turbulent coasts of Beloochistan, and at the mouths of the larger rivers and marine sand-flats off Sind and India, especially those of Bengal and Burma. They are comparatively rare in the open sea; in fact at the Andamans they become scarce, except such species as reside where small streams empty themselves into muddy creeks. On the other hand, in the turbid sea near Moulmein and amongst the islands of the Mergin Archipelago they abound. Siluroids likewise are found from the sea coast to the base of the Himalayas; but as they generally deposit their ova in the waters of the plains, and not (like many carps) in the rivers of the sub-Himalayan range, they very sensibly diminish on nearing the hills, though a few find a home in the upland waters. These latter genera are provided with an adhesive apparatus on the thorax, enabling them to adhere to stones, and preventing them from being carried away by the force of the stream. In these the barbels are short and the air-vessel enclosed in bone. The Siluridæ are well provided with weapons of offence and defence, viz. strong dorsal and pectoral spines, often serrated. Wounds from these spines are regarded by the natives as poisonous. In some districts, indeed, rules are enforced against bringing these fish to the market with their spines intact. It is doubtful, however, if the East-Indian Siluroids possess a distinct poison apparatus, though often ugly sores arise from wounds inflicted by the serrate spines. There is a great difference in the manner in which the different kinds deposit their ova, some few carrying the latter in their mouths. Reviewing the distribution of the different genera and species, Dr. Day shows that seventy-five species are restricted to the Indian Region, including Burma and Ceylon; six are distributed from the Indian Region, excluding Ceylon, to the Malay Archipelago, and one extends from Ceylon to the Malay Archipelago. Consequently one species, and therefore only one genus, of Indian fresh-water Siluroid extends its range to Africa, whereas six reach the Malayan Archipelago. So far results would appear to show that the present race of fresh-water fishes of India is much more closely related to a Malayan than to an African fish-fauna.

In the absence of the author, the Secretary read two papers by Captain Chimmo, R.N. One of these detailed the native mode of dragging for the beautiful Siliceous Sponges (Euplectella) by the natives of the Philippines, and on points concerning their structure; the other was a short description of a supposed new species of Rhizopod.