SPONQIIDA. 
6 Sjpong, 
Esperia lorenzii^ Schmidt, (1) p. 341, pi. xx. fig. 26. Part of develop- 
ment observed. 
Spicules of an unknown Sponge described by H. J. Carter, J. R. Micr. 
Soc. ii. p. 502, pi. xvii. a, fig. 12, as found on a Foraminifer, Aphro- 
sina informis, from Atlantic, North of Scotland ; they resemble those 
of Esperia villosa. 
RhapMdotheca marshall-halli^ Kent, (2) p. 498, pi. xvii. a, figs. 2-4. 
Tethya lyncurium^ Lieberkuhn, (1) p. 626, pis. xxx.-xxxiii. The 
histology and gemmation of this species is fully described. The buds are 
extruded from the parent on the ends of the large spicules ; they com- 
mence to develop in the parent as cellular germs, afterwards forming a 
true endoderm and ectoderm, and going through regular but immobile 
embryonic stages. In op. cit. xvii. p. 161, the specimens from Trieste are 
shown by the same writer to be monoecious ; he gives an account of the 
structure, especially of the connective tissue, of these specimens, p. 151, 
pi. xii. A var. villosa^ Schmidt MS., is noticed, and one, leevis^ Schmidt 
MS., is distinguished as having its dermis divided into plates ; (1) p. 647. 
Heraiastrellina, Carter, (1) p. 147. New group of Suberitida, Carter, 
based on Ilemiastrella, g. n. 
Ecccelonida, Carter, (2) p. 496. New family formed to receive the three 
boring genera, Cliona, Thoosa, Alectona^ and possibly should also contain 
Samus. 
Thoosa, Hancock, (1) p. 352, probably based on spicules of a species of 
Samus, Gray. 
Vioajohnstoni, Schmidt, (1) p. 149. The two forms to which Schmidt 
assigns this name appear specifically distinct from each other. 
Alcyonium purpureum, Lamarck, (1) p. 149. ASuberitic form, resem- 
bling one form of Vioajohnstoni, Schmidt. 
Cliona from marble. J. A. Ryder, Am. Nat. xiii. p. 279, gives some 
account of a species from the north-east coast of the United States, and 
argues on behalf of the manufacture of the canals by the Sponge itself ; 
ova or gemmules were found in it, 
Samus anonymus, Gray, (1) p. 350, pi. xxix. figs. 1-4, re-characterized ; 
from West Indies, Australia, South Seas. Occurs in conjunction with 
Cliona mucronata, Sollas. 
Tetilla, Schmidt, (11) pp. 468 & 479, re-characterized; budding observed 
in both male and female. T. euplocamus, Schmidt, 1. c. p. 468, pi. xxvii. 
fig. 5, exhibits budding ; Rio de J aneiro. 
Dercitus huchlandi, Bowerbank, (12) pp. 22, pi. vii. Its quadriradiate 
spicules show, among other varieties, triradiate and quinqueradiate 
forms. 
Lithistidce (8). Cells distinguished in the surface layer. The linear 
spicules grow out from the surface of the Sponge, and are cast off 
after becoming completely developed. Development of spicules observed, 
but not from so early a stage as the cell-condition ; the point and the 
processes originate independently of the central canal, though this may 
send out secondary offshoots later. In Scleritoderma, the adult spicules 
can be traced from a linear surface form, which becomes more developed 
as it sinks deeper. All Rhizomorina with 4-axial superficial spicules are 
