644 
ZOOLOGICAL LITERATURE. 
close affinities to Axinella ; Microciona (Bk.) would appear to consist of 
several different genera j M. amhigua (Bk.) and M. ab'omiiguinea (Bk.) would 
be referable to Scopaltna (Scb.), whereas M. carnosa (Bk.) is identical with 
Ilalichondria mc?'ustans (Bk.) ; Hgmerapliia (Bk.) is evidently identical witli 
Ilymedesmia (Bk.) (by a misprint it is said to be identical with Microciona 
(Bk.), which = Myxclla (Sch. ex parte), llymcmiacidon*^ (l^^f*) contains a 
great variety of forms, some referable to Iteriiera (Ndo.), some to Suberites 
(Ndo.), and some to JEsperia (Ndo.). Ilalichondria (Bk., Fleming), the typical 
species, H. panicea (Jhnst.), is indubitably a Meniera (Ndo.) ; Isodictya (Bk.) 
also = (Ndo.) ; Desmacidon (Bk.)=JSf?^ena (Ndo.); (Bk.)= 
Papillina (Sch.). 
Hyalornema sieholdii (Gray, 1835). Gray (/. c. p. 287) gives a resume of 
the different descriptions of this remarkable organism, correcting an error he 
fell into (misled by imperfect specimens) in 1859, of placing it along with 
the barked Alcyonaria, and especially noticing Dr. Bowerbank’s description 
of this genus in his ^ British Sponges,’ vol. ii. p. 9, in which Dr. Bowerbank 
would appear to regard the actinozoan polyps of the bark ” portion as 
‘^oscula projecting from the surface of the sponge.” On a consideration of 
the whole question Dr. Gray would feel inclined to believe that the bark 
and axis are part of the same coral, and made by the same animal,” and that 
neither has any direct connexion with the basal portion, which is a true 
sponge. 
Bowerdank, in replying to Gray’s note (/. c. p. 897), states that he hopes 
soon to publish a paper, with the object of showing that the basal mass of 
sponge-tissue, the spiculous axis or rope, and its coriaceous envelope have an 
organic unity, and are portions of one and the same animal, alluding to the 
fact that only among the Protozoa do we meet with animals secreting silex 
in their skeletons. Bowerbank apparently argues that Palythoa fatua (Max 
Sch.) cannot belong to the Actinozoa because siliceous spicula are to be found 
on its inner coat. 
Gray, in his reply (1. c. p. 485), says, whatever theory may be entertained 
about the rope-like bundle of spicula (which he considers the axis of the 
coral), there can be no doubt that the bark on the axis is an Actinozoon 
allied to Zoaiithus. Dr. Bowerbank alone among natm’alists denies this 
fact. 
Euplectella speciosa. Gray (/. c. p. 487) describes some fresh specimens of 
this siliceous sponge which have been lately' received by the British Mu- 
seum j he shows the mistake into which Dr. Bowerbank has fallen by super- 
seding Owen’s generic name Eiiplectella with Alcyoncelhim, and quotes two 
species — (1) E. cucumer (Owen), Seychelles, and (2) E. s2)eciosa (Q. & G.), 
Philippines. 
Clark, 7. c. p. 324, describes Leucosolenia (Grantia) botry aides, Bk. The 
inner layer is entirely made up of the individual members of the sponge- 
colony. To describe the shape and organization of one of these individuals 
would be to describe a monad of Codosiga. Hence, the author argues, it is 
scarcely fair to refer one to the class of the Infusoria and the other to the 
class of Spongiada ; and hence he concludes that all the monociliate flagellate 
Infusoria should be grouped with the Sponges. 
Jlymeniacidon suberea (Bk.). Hughes gives a brief account of the deve- 
lopment of this sponge in an aquarium. Hep. Brit. Assoc. 1865, p. 86. 
