7. Anthozoa (incl. Hydrocorallia). A. Zoantharia. 41 



generation, 8 to 10 complete mesenteries are formed, the number depends 

 on the complete or incomplete character of the mesenteries at the boundaries 

 of the old part. 



The study of the Actinian fauna of the west coas f of Africa leads Pax( 1 ) 

 to divide this coast into 3 regions (1) the north west coast (2) the gulf of 

 Guinea and (3) South Africa. In the first region typical European species are 

 met with , e. g. Ammonia sulcata, the southern limit of which is Madeira. The 

 tropical zone (2) is entirely free from European influence. The fauna of the 

 third zone presents Antarctic affinities. The fauna of north west Africa is more 

 closely related to that of western Cape Colony than to that of the intervening 

 tropical zone, for instance, Epixoanthus occurs in the Azores and near Cape 

 Town. The factors which determine this faunistic differentiation into 3 regions 

 are chiefly climatic. The most southern limit of the European actinian fauna 

 on the west coast of Africa is the Cape Verde Islands, to this limit extend 

 Actinia equina and its var. Cari and Adamsia Eondeletii. Phymactis capensis 

 occurs on the west coast of S. Africa and off Chile under similar climatic con- 

 ditions (cold surface current) in both cases. The author describes Euphellia n. 

 cinclidifera n. from Teneriffe; it is one of the Phelliinse, near Phettia, with a 

 clear division of the body into scapus and capitulum, and possesses cinclides 

 arranged in longitudinal rows. After examining the original specimens of 

 Zoanthus thomensis and glaucus from the gulf of Guinea the author merges the 

 latter with the former. Paraphcllia polyptycha n. is described from S. Africa. 

 24 species of Actiniae are now known from W. Africa namely - - 1 Cerianthus, 

 17 Actiniinse and 7 (plus 3 doubtful) Zoanthacese. 



Pax( 2 ) records and describes from E. Africa - - Edwardsiella 1, Bolocera 1 n., 

 Gephyra 1 n., Alicia 1, Gyrostoma 2 (1 n.), Thalassiantlms 1, Zoanthus 3 (1 n.; 

 ova and testes occur on the same mesentery), Isaurus 1, Palythoa 8 (5 n., 

 1 n. var.). In the homogeneous matrix of Bolocera there are, especially in the 

 tentacles, numerous elliptical gelatinous capsules about 25 in x 18 ,, each of 

 which contains 1 to 4 rounded nucleated cells. The mesogloea in this species 

 is probably of endodermal origin. The author also describes a hypertrophic 

 Actinian larva, 1,1 cm. long, from Zanzibar [see Bericht f. 1908 Coel. p 29]. 

 The Zoanthids, numerous in species and in individuals, are the feature of the 

 East African Actinian fauna. 



Pax( 3 ) describes a specimen of Polyparium ambulans from Bowen on the 

 coast of Queensland. It is 36 cm. long, 5,1 cm in girth, semicircular in trans- 

 verse section ; its upper surface is covered with small rounded elevations, each 

 with a terminal pore, and its lower surface forms a creeping sole. The interior 

 is divided into a number of chambers corresponding with the rounded elevations. 

 Sections of one of the elevations show that it has no trace of the structures 

 characteristic of Anthozoan polyps, but that it is essentially an actinian tentacle. 

 P. amb. is therefore not an Anthozoan colony (Korotneff and Perrier), but a 

 single actinian, not greatly elongated in a lateral direction (Haacke), for it has 

 a sphincter muscle along only one edge ; it is the outer region of the oral disc 

 of an actinian (Ehlers and Carlgren) and was originally in the form of a ring 

 but became broken at one point and assumed, during locomotion, a spiral con- 

 dition. On one of the ends a tuft of tentacles has been produced such as is 

 regularly formed on the wound surface in cases of incomplete separation. From 

 the external characters of the specimen and the structure of its sphincter muscle 

 there can be little doubt that it is the outer region of the oral disc, cut off 

 by autotomy, of a large Stoichactis, probably S. Kenti. The author describes, 

 from Gomera (Canary Islands) Priapus equinus, Anemonia sulcata, Aiptasia 



