The phylogenetic origin of the Cannobotryida may be found either in the Zygospyrida or in the Monocyrtida; they differ from these two similar groups in the lobation of the cephalis, which is effected by the development of internal septa and external constrictions. _Synopsis of the Genera of Cannobotryida._ Cephalis without porous tubes, 486. _Botryopera_. Cephalis with a variable number of porous tubes, 487. _Cannobotrys_. Genus 486. _Botryopera_,[104] n. gen. _Definition._--#Cannobotryida# without tubes on the cephalis. The genus _Botryopera_ is the simplest form among the #Botryodea#, the shell consisting of a lobate cephalis only, without tubes or radial appendages. It may be derived either from _Dictyospyris_ or from _Archicapsa_ by development of the horizontal fold in the frontal face of the shell, and the corresponding internal frontal septum, which separates the larger occipital lobe from the smaller facial half; the latter may be divided again into paired frontal lobes, lateral buccal lobes, &c. _Botryopera_ may be the common ancestral form of many #Botryodea#. 1. _Botryopera cyrtoloba_, n. sp. (Pl. 96, fig. 1). Cephalis trilobate; the posterior odd occipital lobe helmet-shaped, about twice as large as the two paired anterior frontal lobes, which are subovate and covered by the upper half of the former. Pores small and numerous, subregular, circular; some larger pores at the base. _Dimensions._--Length of the shell 0.08, basal breadth 0.06. _Habitat._--Central Pacific, Station 265 to 274, depth 2350 to 2925 fathoms. 2. _Botryopera triloba_, Haeckel. _Lithobotrys triloba_, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 30. Cephalis trilobate; the occipital lobe subcylindrical, one and a half times as long as the two frontal lobes, which are slender, ovate and not covered by the former. Pores small and numerous. _Dimensions._--Length of the shell 0.05, breadth 0.03. _Habitat._--Fossil in Tertiary rocks of the Mediterranean (Sicily, Greece, &c.) {1109}3. _Botryopera quadriloba_, Haeckel. _Lithobotrys quadriloba_, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 84. Cephalis quadrilobate; the occipital lobe helmet-shaped, one and a half times as long as the two paired hemispherical buccal lobes, and twice as large as the anterior frontal lobe. Pores not numerous, rather large, circular. _Dimensions._--Length of the shell 0.06, breadth 0.04. _Habitat._--Fossil in Barbados and North America (Virginia). 4. _Botryopera quinqueloba_, n. sp. (Pl. 96, fig. 2). Cephalis quinquelobate; the occipital lobe helmet-shaped, and twice as long as the two hemispherical frontal lobes, three times as long as the subspherical lateral buccal lobes. Pores scarce, small, circular. _Dimensions._--Length of the shell 0.07, basal breadth 0.05. _Habitat._--North Pacific, Station 253, depth 3125 fathoms. 5. _Botryopera multiloba_, n. sp.