26 Coelenterata. 



found at a depth of 500-800 m. that is, where the temperature is similar to 

 that of the habitat of this species in Norway, where it is found at a depth 

 of 40-80 fms. In Sagartia nitida n. the number of septa on the two sides 

 of the axis is unequal due to the presence, on one side, of a zone of more 

 rapid growth perhaps correlated with the occurrence of longitudinal fission. 

 Shortly after fission the sagittal axes of the products are parallel, later they 

 are inclined to one another and finally lie in a straight line. No gonads were 

 found which suggests that asexual reproduction plays an important part in 

 this species, the individuals of which were found, to the number of 60-80, close 

 together on the stein of a Gorgonia. In the deepest part of the ectoderm 

 of Chondrodactis n. g. (3 sp. ; fam. Sagartinse) there are in some of the cells 

 round or elongate granules, probably mitochondria, which apparently fuse with 

 one another to form the spiral filament of the nematocyst cells. The author 

 also describes Halcampella 2 (1 n.), Actinia 1, Anemonia 1, Condylactis 2 (1 n.), 

 Amphianthus 1 n., Stephanactis 1 n., Cribrina 2 (1 n.) ; Anthopleura 1 n., Leiotealia 

 1 n., Phyllactis 1 n., Cradactis 1 n., Paractinia 1, Cymbactis 2 n., Actinostola 1 n., 

 Metridium 1, Cerianthus 2, Gemmaria In. Hargitt( 1 ) describes Anemonia 1 n. 



Clubb describes the brood pouches present in specimens of Cribrina octoradiata 

 from the Falkland Islands. Immediately below the pseudacrorhagi there is a 

 well-marked constriction of the body wall (which is also present in specimens 

 of Parantheopsis cruentata from the Falkland Islands) in which are 16 pores, 

 one pore corresponding to each line of verrucse. Each pore leads into an in- 

 vagination of the body wall forming a brood pouch , about 3 mm. in diameter, 

 usually containing two embryos, which, in the specimen examined, show several 

 complete mesenteries. In C. hermaphroditica ova and sperms are present, often 

 both on the same mesentery, and zooxanthellse occur throughout the endoderm 

 but are especially abundant in the tentacles. The specimen of Actinostola 

 chilensis examined was not hermaphrodite like that described by McMurrich; 

 large ova were present but no spermatozoa. The author also describes Paractis 2 

 (1 n.), Cystiactis 1 n. and Rhodactinia 1. 



Walton ( J ) describes, from Plymouth, specimens of Sagartia coccinea, sphyro- 

 deta and lucicB. The last-named, possibly introduced, was in active division 

 and examples with 4, 6 and 8 stripes were more frequent than those with the 

 normal 12. Two large specimens had each 17 pairs of stripes, one of these 

 later divided into two, each with 17 stripes. Paraphellia expansa, Epizoanthus 

 couchii and rubicornis and Parazoanthus dixoni are described. See also 

 Walton ( 2 ) and in regard to symbiosis between Adamsia and Eupagurus Bericht 

 f. 1907 Arthropoda p 36 Schaffer. 



According to Child f 1 ) the distension by water in the coelenteron is an essen- 

 tial factor in form regulation in Cerianthus aestuarii and solitarius] in its 

 partial or total absence the formation of disc and tentacles is retarded or in- 

 hibited. The internal pressure is essential not only for the formation of new 

 parts but also for the persistence of the old. Partial or total atrophy of the ten- 

 tacles follows decrease or absence of the distension, the atrophied structures 

 develop anew when distension is again permitted to occur. The body wall 

 of cest. is much thinner than that of sol. and is also much more sensitive to 

 changes in internal pressure ; in the absence of distension the body wall under- 

 goes rapid atrophy and disintegration. In nature the walls of the burrow in 

 which the animal lives aid the body wall in supporting the pressure resulting 

 from distension, especially in the aboral region. If the animals are kept in 

 water, without sand in which to burrow, the internal pressure never reaches 

 its normal amount. Under these conditions the tentacles are more or less 



