Definition.—Pylobotryida without tubes on the cephalis, and with the mouth of the abdomen open.
The genus Botryocyrtis, founded by Ehrenberg upon two Indian species, is the simplest among the Pylobotryida. It may have been derived from Botryopyle by the development of an abdomen (or a third shell-joint), the mouth of which remains open.
1. Botryocyrtis serpentis, Ehrenberg.
Botryocyrtis serpentis, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287, Taf. x. fig. 21.
Cephalis quadrilobate; the odd frontal and the two paired buccal lobes subspherical, about half as large as the odd occipital lobe. Thorax inflated, about as long as the cephalis and half as long as the ovate abdomen. Mouth of the latter constricted, of half the breadth.
Dimensions.—Length of the shell 0.12, breadth 0.06.
Habitat.—Indian Ocean (Zanzibar), depth 2200 fathoms, Pullen.
2. Botryocyrtis theocampe, n. sp. (Pl. [96], fig. 19).
Cephalis quadrilobate; the odd frontal and the two paired buccal lobes hemispherical, about half as large as the helmet-shaped occipital lobe. Thorax cylindrical, of equal length and breadth, one and a half times as broad as the cephalis and as the cylindrical abdomen. Pores rather large, irregular, roundish.
Dimensions.—Length of the shell 0.12, breadth 0.06.