SPONGIIDAj GREGARINIDA. 
485 
of a central stem or axis, around the distal portion of which the sponge-body 
is disposed in separate whorls, or in more or less regular spiral convolutions. 
Skeleton compound, consisting of a primary network of ceratose fibre, with 
siliceous spicula irregularly imbedded in it, and an accessory one of siliceous 
spicula only. Spicula of one form, simple, spinulate, arcuate. Allied to 
Diplodemia, Bowerb. Types C. vcrticillata^ N. Australia, and C. plicata^ 
liab. — ?, spp. nn., id. 1 . c. pi. 48, figs. 1 & 2. 
Aulorhipis elegans, n. g. & sp., Ehlers, SB. Soc. Erlang. 1871, iii. ; Ann. 
N. H. (4) vii. pp. 302 & 303 ; Z. wiss. Zool. xxi. pp. 540-667, pi. 42. Sponge 
lining the inner surface of a worm-tube, projecting from its superior opening 
in the form of a small stem, which forks into two branches bending down- 
wards in the same plane, each of which gives off 8 or 10 twigs directed up- 
wards, standing at regular distances apart, one or two of which give off lateral 
branchlets, springing at an acute angle in the same plane, also directed up- 
wards, and terminating in a capillary form. No pores, oscula, or internal 
canal-system. Bass’s Straits and Narson Island (= Terehellajlohellum^ Baird, 
P. L. S. viii. p. 167, pi. 6. fig. 1). Allied to the Ceraospongia, especially to the 
fossil genus IStromatopora^ and is a unique form among living sponges. 
Neio species : — 
Tethya casulttj Carter, Ann. N. H. (4) viii. p. 99, pi. 4, S. -African coast. 
Dercitus niger, id. 1. c. vii. p. 3, pi. 4. figs. 1-6, Devon {? = Ilymeniacidon 
bucJdandi, Bowerb., var.). 
Stelletta aspera, p. 7, pi, 4. figs. 7-14, lactea, p. 9, pi. 4. figs. 16-22, Devon : 
id. 1. c. 
SpongiUa (?) arnclmoiden, II. James-Olark, Am. J. Sc. (3) ii. p. 427, pi. 2, 
Massachusetts. 
Enpet'ia socialis, Carter, 1. c. p. 276, West Indies. 
lanthella terrucosa^ Giebel, Z. ges. Naturw. (2) iv. p. 380, Indian Ocean ? 
or New Holland P 
GREGARINIDA. 
A^an Beneden Reclierclies sur revolution des Gregarines/^ 
Bull. Ac. Belg. xxxi. pp. 325-359, plate; transl. Q. J.Micr. Sci. 
xi. pp. 242-260, pi. 12, and noticed, M. Micr. J. vi. pp. 104 & 
105) describes tlie development of Gregarina gigantea, which 
occurs in the small intestines of the lobster. The earliest stage 
of the germs resembles Protamceba, Hack. ; but subsequently the 
protoplasmic mass shows a tendency to separate into a cortical 
and a medullary substance. Others exhibit one or two pro- 
longations resembling pseudopodia, but which, from their con- 
stant form and the nature of their movements, have really more 
affinity to the mobile appendage of the Noctilucce, When one 
of these prolongations has attained a certain length, it detaches 
itself; and the other then becomes developed in its turn. The 
latter does not detach itself from the cytode, but develops by 
gradually absorbing the body of the cytode, as the embryo of a 
vertebrate animal absorbs the contents of the vitelline vesicle. 
