BIOLOGY. 
Spong. 11 
C. Physiology. 
(i) General Accounts. — Vacant. 
(ii) Nutrition. — Ingestion of food in sponges; “the ingestion of 
solid particles which traverse the canals of Sponges, is the function of the 
choanocytes, while the transport into the interior of the body of the 
substances ingested, belongs to the wandering cells”, pp. 437-451 : 
digestion in Sponges : “ in Calcarea the function of ingestion and, for the 
most part, that of digestion, are performed by the choanocytes : in non- 
Calcarea the choanocytes ingest, the amcebocytes digest. The digestion is 
intracellular.” The digestive action of sponges upon various substances, 
pp. 452-501 : reserve materials in sponges, pp. 549-554 ; Cotte (9). 
(iii) Respiration. — Influence of asphyxiation in producing degene- 
ration of collar-cells, etc ; Cotte (10). 
(iv) Secretion and Excretion. — Pigments of Sponges, their 
nature and function, pp. 502-531 : Diastases of sponges and their action, 
463-501 : secretion in sponges, pp. 502-548 : excretion of sponges, ex- 
pulsion of waste matters, and nature of the products of disassimilation, 
pp. 555-564 ; Cotte (9). — Action of phagocytes in absorbing collar-cells 
which have degenerated as the result of asphyxiation ; Cotte (10). — The 
presence of tyrosinase in Suberites domuncula, Tethya lyncurium , and 
Cydonium gig as ; Cotte (11). — Presence of manganese in Spongelia palles- 
cens elastica massa F.E.S., Tethya lyncurium, Reniera simulans , Suberites 
domuncula : the gemmules of the last-named especially rich in it : manga- 
nese found especially in tissues of rapid growth : iron in tissues of Tethya 
lyncurium \ Cotte (12). — Starch probably not elaborated by sponges: when 
found, its presence due to commensal algse ; Cotte (13). — On the nature 
of lipochromes ; Cotte (14). 
(v) Irritability, Contractility, etc.— Movements of flagella, 
closure of pores, and currents of canal-system, pp. 424-436. Contractility 
of choanocytes, pavement epithelium, and ground-substance, pp. 432-436; 
Co^tte (9). 
D. Bionomics. 
Vacant. 
E. Reproduction and Development. 
(i) Germ-Cells, Fertilization. 
Spermatogenesis of Sycon raphanus and Ephydatia jluviatilis , and 
structure of the spermatozoa of the latter ; Gorich (19) pp. 6£-67, fig. 3 
[not fig. i, as stated in the text; vide Gorich (20)]. 
(ii) Embryology. 
(a) General Accounts. — Vacant. 
(b) Early stages, larvae, and metamorphosis. — Structure of 
the larvse of Leucopsacus orthodocus Ij., as seen in sections of the sponge; 
Ijima (22) pp. 43-46. — Larvse of Thoosa armata , remarkable for possessing 
an armature of plate-like spicules, in addition to other forms of spicules ; 
Topsent (52). — Alterations in embryos of Sycandra raphanus as the result 
of asphyxiation ; Cotte (10) p. 737. 
