SPONGIIDA. 
8 Spong. 
Neapolitan specimens, but found ova in both elongate and massive, 
yellow and pink specimens. 
Chalinula robustior , Schmidt?, (17) p. 39, pis. i. fig. 23, iii. fig. 113, 
Barents Sea. 
Chalinula sp., (17) p. 40, pi. iv. figs. 148-151, Matosjkin Shar. 
Spongia rubens, Pallas, W. Indies and S. Australia, = Chalina, accord- 
ing to Carter, (2) p. 276, pi. xi. fig. 7. 
Tuba y Duchassaiug & Michellotti. Five of these authors’ species de- 
scribed by Carter, (2), from W. Indies. T. lineata , digitalis , armigera , 1. c. 
pi. xi. figs. 4-6. 
Renierid^e. 
Yosmaer (16) finds the canal system in this family to resemble strongly 
that of Euplectella, as described by Schulze. The ciliated chambers are 
sac-shaped, and always open into broad canals by wide openings. 
Reniera. The great variety of coloration found in this genus is 
remarked upon by Krukenberg, (9) p. 37. A species resembling R. aqui- 
ductus , found at Triest, owes its pale red or violet colour to a variety of 
Floridiue, which is soluble in sea-water, and is but little altered by acids 
and alkali, but becomes dull yellow on boiling ; it gives no distinct 
absorption band in the spectrum. See also R. purpurea, sp. n. 
Reniera calyx , Schmidt. Carter, (4) p. 124, doubts the correctness of 
the generic determination of the species, and refers it provisionally to 
his new group Phlceodictyina. 
Reniera Jiligrana , Schmidt. Described from Corfu by Marshall, 
(12) p. 221. It is dioecious; the sexual period is August and Sep- 
tember. Segmentation is regular ; the ovum largely increases in size 
during the process ; ultimately a blastula is formed, having a segmenta- 
tion cavity surrounded by a uni -laminar continuous ectoderm. When 
the component cells of this blastula reach the number of about 2000, 
they become elongated and prismatic, and are of equal size in all 
parts; the nuclei now lose their granules ; the contents (called “coeno- 
blast ”) of the segmentation-cavity also now become dark and granular, 
aud nuclei appear in it ; the granules are probably derived from the ecto- 
derm, and the nuclei are perhaps due to free nucleus-formation. The 
mature embryo has a round brownish violet spot at the anterior pole. 
When liberated into the canals of the parent from the egg-capsule, it is, 
for the first time, seen to possess a covering of cilia, and a ring of spocial 
large cilia just behind the pigment spot. During a period of free exist- 
ence, the larva exhibits amoeboid movements, attributed with probability 
to the action of the coenoblast ; the ectoderm cells now alternately lose 
and regain their cilia. Finally, the larva attaches itself by means of 
amoeboid processes of the coenoblast, which protrudes at the hinder end ; 
the cilia of the ectoderm disappear, aud its cells lose their contours and 
blend into a continuous mass, containing round nuclei ; the coenoblast, 
which has emerged at the anterior pole, shows very active amoeboid 
movements. The sponge rapidly flattens out; the ectoderm loses its 
nuclei. The coenoblast is, henceforth, the only part which exhibits im- 
portant changes ; a little behind its anterior exposure a round flat space 
