CXXVl 
THE VOYAGE OF H.M.S. CHALLEHGEK. 
Genus 4. Craniella, 0 . Schmidt. 
Craniella, 0. Schmidt, Spong. Atlant. Gehiet., p. 66, 1876. 
„ Sollas, Ann. and Mag. Nat. Hist., ser. 5, voL ix. p. 149, 1882 ; Sci. Proc. Roy. Dubl. 
Soc., p. 181, 1886. 
The cortex is differentiated into an inner fibrous layer, traversed radially by cortical 
oxeas ; and an outer collenchymatous layer, excavated by intercortical cavities. 
The pores lie in groups, perforating the roofs of the intercortical cavities ; the oscules 
are distinguishable from the pores, and are usually few in number. 
The mesoderm of the choanosome consists of sarcench 5 une. The chamber-system is 
aphodal. 
Type — Craniella cranium, Lamarck. 
Family II. S a m i d Sollas. 
Samidx, Sollas, Encyclopaedia Britannica, vol. xxii. p. 423. 
History . — The genus Samus, on which this family is founded, was included by Gray 
in the family Clioniadae, Gray.^ With Cliona, the type of this family, it has evidently no 
near relation. Carter having founded a family very similar to the Clioniadae, viz., the 
Eccoelonidae,^ to contain the three genera, Cliona, Thoosa, and Alectona, subsequently 
added Samus to it and another new genus Dotona.^ The family Eccoelonida not being- 
established on morphological characters, but on a peculiarity of habit only, could scarcely 
be expected to stand, and a very slight examination is sufficient to convince us of the 
want of morphological affinity between its components. The family evidently cannot be 
defended, but even were this not the case, the genus Samus would have to be removed 
from it, since it possesses no essential character in common with its associates. The 
presence of the amphitrisene, the only megasclere it possesses, indicates its place with the 
Tetractinellida ; the sigmaspire similarly with the Sigmatophora ; within this demus it 
must be included as the representative of a distinct family. 
D^nition . — Sigmatophora in which the characteristic megasclere is an amphitrisene. 
Genus Samus, Gray. 
Samus, Gray, Proc. Zool. Soc. Lond., p. 526, 1867. 
„ Carter, Ann. and Mag. Nat. Hist., ser. 5, vol. vi. p. 59, 1880. 
With the definition of the family. 
Type — Samus anonymus. Gray. 
1 Gray, Proc. Zool. Soc. Lond., p. 526, 1867. 
^ Carter, Journ. Roy. Micr. Soc., vol. ii. p. 496, 1879. 
3 Carter, Ann., and Mag. Nat. Hist., ser. 5, vol. vi. p. 56, 1880. 
