190 SUMMARY OF QUERENT RESEARCHES RELATING TO 



Plexaurids and Gorgonids is not a secretion-product of an ectodermic 

 axial epithelium. It is a mesodermic structure. Numerous spicules, 

 assumed to be of mesodermic origin, are often embedded in the horny 

 cortical layer of the axis, as Studer and Schneider have shown. The 

 axial epithelium may be absent, and in any case it is derived from the 

 mesogloea. In PUxaura Jiavida, in the horny cortical layer and in the 

 zone between central strand and cortical layer, the author found distinct 

 cells, whose connection with the mesogloea was certain. They gradually 

 become more and more horny. Thus, according to the author, the dis- 

 tinction between Scleraxonia and Gorgonacea is greatly weakened. 



South African Gorgonacea.* — J. Stuart Thomson describes Siiheria 

 capensis sp. n., Muriceides fusca sp. n., Eunicella papiJlosa Esper, Fsam- 

 mogorgia pukJtra sp. n., Euplexaura media sp. n., Malacogorgia capensis 

 Hickson, Stachyodes gilchristi sp. n., and Tlwuarella hicksoni sp. n. 



Australian Hydroids.t — James Ritchie reports on the collection made 

 by the ' Thetis,' which includes 38 species ard varieties, 15 being dis- 

 tinctively Australian. The main interest of the report lies in the 

 additional information which it offers regarding the morphology of species 

 of great rarity. It has been found necessary to establish eight new 

 species and varieties, distributed among the genera Lidorella (1 sp.), 

 Cryptolaria (1 sp. and 2 vars.) — a genus not hitherto known from the 

 Austrahan area, SerhdaTella (1 sp. and 1 var.), Halicornaria (1 sp.), and 

 GJadocarpus (?) 1 sp., also recorded for the first time from i^ustralia. Of 

 these the most interesting, from a general point of view, is the dimorphic 

 variety of Cryptolaria crassicaulis, which throws light on the phylogenetic 

 origin of Cryptolaria, and emphasizes the close relationship that exists 

 between that genus and Lafoiia. The gonosome of the widely-distributed 

 Lafo'ea serrata is described for the first time. Tiie comparative rarity 

 of Gymnoblastic forms and of minute epizoic species is noticeable. In 

 addition to Hydroids proper, the collection included Stylaster eximias, 

 new to Australia. Although an unusually large proportion of the known 

 Hydi'oid fauna of south-east Australia is peculiar to Australia, there are 

 also many species common to it and to other oceanic regions. Of the 

 22 species concerned, 18 have been found in the Indian Ocean, 13 in the 

 Atlantic, 10 in the Pacific, and 6 in the neighbourhood of New Zealand. 



Hydroids of American West Coast. J — C. McLean Eraser reports 

 on a collection from Vancouver Island Region, and gives a list of species 

 known to occur on the west coast of North America, with the full re- 

 corded distribution of the species along the coast. He describes seven 

 new species, and adds ten other new records. Out of a total of 196 

 species, there is a record of 155 species from Vancouver Island region 

 and north of it, and 88 south of that region. No less than 47, or 24 p.c. 

 of the whole number, are common to the two regions. 



* Proc. Zool. Soc, 1911 pp. 870-93 (3 pis.). 



t Memoirs Australian Museum, No. 4 (1911) Scientific Eesults of ' Thetis ' 

 Expedition, pt. 16, pp. 807-69 (6 pis. and 1 fig.) 

 : Bull. Univ. Iowa, vi. (1911) pp. 1-91 (6 pis.). 



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