REPORT ON THE RADIOLARIA. 1111 



on the base of the shell (an odd posterior caudal tube and two paired anterior pectoral tubes). The 

 two lateral buccal lobes- are twice as large as the two anterior fi-ontal lobes, and half as large as the 

 posterior odd occipital lobe. The four tubes in this and the following species correspond probably 

 to the four spines of Cortina (p. 950). 



Dimensions. — Length of the shell 0'07, basal breadth 0'06. 



Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 2925 fathoms. 



6. Cannohotrys tetracanna, n. sp. 



Cephalis multilobate, with four cylindrical curved tubes conical at their wider base, correspond- 

 ing to those of the preceding species and to the four spines of Cortina. The odd occipital lobe is 

 of about the same size as the anterior part of the shell, which is cleft into three pairs of roundish 

 lobes, one pair of anterior larger frontal lobes, and two pairs of smaller lateral buccal lobes. Pores 

 very few and minute. 



Dimensiom. — Length of the shell O'll, basal breadth 0'07. 



Habitat. — North Pacific, Station 253, depth 3125 fathoms. 



7. Cannohotrys pentacanna, n. sp. 



Cephalis quinquelobate, with five cylindrical slender curved tubes, three of which are placed in 

 the sagittal plane (a superior apical, a posterior caudal, and an anterior sternal), whilst the other 

 two are paired and diverge laterally (two pectoral tubes). The five tubes correspond exactly to 

 the five typical spines of Stephanium (p. 952). The helmet-shaped occipital lobe of the shell is 

 twice as large as each of the two anterior frontal lobes, and three times as large as each of the two 

 lateral buccal lobes. Pores numerous. 



Dimensions. — Length of the shell 007, basal breadth 004. 



Habitat. — ^Western Tropical Pacific, Station 225, depth 4475 fathoms. 



Family LVII. Lithobotryida, n. fam. 



Definition. — Botryodea dithalamia, the shell of which is composed of a lobate 

 cephahs and a simple thorax, without abdomen. 



The family Lithobotryida comprises those Botryodea in which the shell is 

 divided by a transverse annular constriction into a lobate cephalis and a simple thorax. 

 They correspond therefore to the Dicyrtida among the Cyrtoidea, and to the 

 Phormospyrida among the Spyroidea. The thorax, or the second shell-joint, is in 

 all these three families a secondary production, arising from the base of the cephalis ; 

 therefore the Lithobotryida must be phylogeneticaUy derived from the Cannobotryida. 



Several species of Lithohotrys were first described by Ehrenberg as Lithobotrys 

 and Lithocorythium. These two genera are, however, identical, as has been 



