1 8 Coelenterata. 



dependent upon fission. Division is aboral-oral and is usually accomplished within 

 24 hrs. By feeding to repletion, division already begun could be delayed, even appa- 

 rently prevented. When cut longitudinally into halves regeneration is rapid, even 

 small fragments artificially obtained produced normal individuals. Normal division 

 was observed only in diglyphic forms. Basal budding and fragmentation are common 

 methods of multiplication of this species. See also Dicquemare and Parker. 



Dahl states that there are several appearances presented by the coral reefs of 

 the Bismarck Archipelago which are easily explained by Darwin's theory but are 

 difficult to reconcile with those of Murray and Agassiz. See also Agassiz and 

 Darwin. 



B. Alcyonaria. 



See Liversidge, May and Putter. 



Hicksonf 1 ) describes several Alcyonaria and Hydrocorallinae from the Cape of 

 Good Hope, viz, Heteroxenia 1 n., Alcyonium 2, Acrophytum n. 1, Sareophytwn 1, 

 Melitodes 1, Spongioderma 1, Gorgonia 2 (1 n.), Juncella 1, Ewnicella 1, Primnoisis 

 1, Villogorgia 1, Virgularia 1, Cavernularia 2, Allopora 1. The autozooids of H. 

 capensis appear to be more retractile than those of any previously described species. 

 Red and yellow specimens of M. dichotoma were taken in the trawl at the same 

 time and place. This confirms the opinion gained by the study of their anatomy 

 that these are merely varieties, the difference in colour being due to the spicules. 

 Larger and smaller polyps are present on the terminal branches, but the smaller 

 ones are merely undeveloped ; both possess 8 tentacles and 8 mesenteries. Dried 

 specimens would present a condition very similar to that recorded by Ridley in M. 

 albitincta in which dimorphism of the polyps was described. G. capensis n. is 

 viviparous, each embryo lying in a special enlargement of one of the intermesen- 

 terial spaces of a polyp. These are so large that it is improbable they are dis- 

 charged by the mouth, perhaps the ccenenchym is ruptured from time to time to 

 allow the escape of the embryos and is afterwards regenerated. In fact, on some 

 of the older branches there is a longitudinal slit of some length in the ccenenchym 

 covering the axis and below this the ccenenchym is thin and there are no embryos. 

 The eggs of Alcyonaria, being provided with a considerable quantity of yolk and 

 having no spicules nor offensive weapons, may form a substantial meal to certain 

 species of fish. 



Hickson & Miles find that in Clavularia viridis the dorsal mesenterial filaments 

 extend from the lower end of the stomodaeum to the stolon and they bear tag- 

 like processes laterally. The ventral and lateral mesenterial filaments are short 

 and are situated on the edge of the corresponding mesenteries some distance below 

 the stomodaeum, the gonads occur on these mesenteries nearer the stolon. Telesto, 

 notwithstanding its resemblance to a Gorgonacean, is undoubtedly an Alcyonacean, 

 for it bears no axis of any kind nor any axial canal like that of Ccdogorgia. Small 

 endodermal canals place the coelentera of the polyps in communication. The spe- 

 cimens reported upon include - - Tubipora 1, Clavularia 1, Telesto 2 (1 n.), Spon- 

 godes 5 (1 n.), Nephthya 2, Ghironephthya 1, Alcyonium 4 (1 n.), Sarcophytum 3, 

 Lobophyt-um 4. 



Lacaze-Duthiersi - describes the structure of Sympodiwn coralloides. There is 

 beneath the ectoderm a network of canals lined by ciliated cells. The dorsal me- 

 senterial filaments are grooved and thicker than the others, the dorsal mesenteries 

 do not bear gonads. The coral is dioscious. In May, June and even in July ova 

 or larvae and testes may be observed. The red colour of the ova is due to gra- 

 nules in the vitellus. The testes are less than the ovaries and are white. Each ovum 

 or testis is surrounded by a film of mesogloea and a layer of endoderm cells, this 



