HYDROZOA. 
Gcel. 18 
(tertiary). D. contorta^ sp. n., Pourtales, Bull. Mus. C. Z. v. 9, 
p. 210, pi. i. fig. 9, ofiP Havana, 176 fath. 
(6.) Dactylopores of two kinds, larger and smaller. 
6. Ldbiopora^ g. n., Moseley : Larger dactylopores within nariform 
projections arranged in regular rows ; smaller dactylopotes at the 
sides of these (soft parts unknown). L. antarctica (Gr.) (de- 
scribed as a Bryozoon, Porella^ allied to P. cercicornis), pi. ii. 
fig. 5. 
7. Spinopora, g. n., Moseley lAcanthopora previously] : Larger dac- 
tylopores within long spinelike projections ; smaller dactylopores 
in simple cavities at their bases ; gastrozooids with 6 tentacles. S. 
echinata, sp. n., id. p, 447, pis. xxxiv. fig. 2, xxxv. fig. 4, & xxxviii. ; 
with Sporadopora, Errina labiata, &c. 
(b.) Pores occurring in regular cyclosystems only. 
(c.) Both kind of pores with styles. 
8. Allopora: Cyclosystems budding from one another somewhat 
irregularly ; gastrozooids with 12 tentacles. Ten species and two 
fossil (tertiary described as species of Madracis). A. profunda^ 
sp. n., Moseley, p. 455, pi. xxxiv. fig. 7, & pi. xxxix. With Spo- 
radopora, &c. 
9. Stylaster, Gr. : Corallum increasing by regular alternate gemma- 
tion of the cyclosystems from one another : gastrozooids with 8 
tentacles. Twenty species known [when the new species of 
Studer (Zool. Rec. xiv. Ccel. p. 14) are added to those enume- 
rated by Moseley]. S. densicaulis, sp. n., Moseley, p. 449, pi. 
xxxiv. fig. 5, xl. With Sporadopora, &c. 
10. Stenohelia, Kent. Branching flabelliform ; dactylopores without 
a columella, or with a very rudimentary one. Two species 
known. S. profunda, sp. n., Moseley, p. 503, 450 fath., off St. 
Thomas (no description) {S. complanata, Kent, is referred to 
Stylaster). 
(d.) Styles absent in both kinds of pores ; gastropores with 
two chambers ; gastrozooids without tentacles. 
11. Cryptohelia, Edw. & Haime : Summits of cyclosystems covered by 
a lid (= Endohelia, E. & H. ?). C. pudica, p. 462, pi. xlii. 
Three species known [when 0. virginis, Lindstr., Zool. Rec. xiv. 
1. c. is kidded]. 
12. A stylus, g. n., Moseley : Cyclosystems without a lid. A. sub- 
viridis, sp. n., id. p. 457, pis. xxxiv. fig. 4, & xli. fig. 1, off Meangis 
Island, 600 fath. 
13. Conopora, g. n., id. {— Cyclopora, Verr. ?) : Differs from the two 
preceding genera in having no lid or tongue-like process, and 
in not forming a regular flabellum. C. tenuis, sp. n., id., p. 503, 
off Kermadec Island, 650 fath. Cyclopora bella (Dana) per- 
haps also belongs to this genus. 
Certain fossil species described as Thalamipora {Foraminiferd) and 
Heteroporella {Bryozoa) also possibly belong to the Stylasteridoe. As the 
chief points in the anatomy of the StylasteridcB have been briefly alluded to, 
1878. [voL. XV.] c 4 
