80 JOURNAL OF MARINE ZOOLOGY AND MICROSCOPY. 



Explanation of Plate VII. 



Structure of Anthozoa. 



Fig. 1. Trans, sec. of Siphonactinia triphylla, through region of 

 oesophagus, i.e., cut along the line indicated by the letters 

 A— B in Fig. 3. X 3f. 



Fig. 2. Trans, sec. of same, at a lower level, i.e., along line indicated 

 by C— D in Fig. 3. X 3|. 



Fig. 3. Diagram of anemone structure, shown by a vertical section 

 along the plane indicated by letters A — B in Fig. 1. 

 A mesentery is cut through longitudinally on the left 

 side ; on the other, the section passes through an inter- 

 septal space. 



Fig. 4. S. triphylla, actual size. 



Fig. 5. Surface section through a colony of Alcyonium digitatum, 

 the polyps retracted wholly. For the sake of clearness, 

 the tentacles which are retracted within the oesophagus, 

 are omitted from the section. D, dorsal region ; V, ven- 

 tral region. X 9. 



Fig. 6. Trans, sec. thro' portion of stalk of a colony of A. palmatum. 



Lettering : — cce, ccenosarc ; cr, mesenterial filament or craspedon ; 

 dm,, dorsal directive mesenteries ; dm ', ventral ditto ; e, ectoderm of 

 body walls ; e', ectoderm of oesophagus ; en, endoderm ; gg, genital 

 gland ; im, intraseptal chamber ; is, interseptal chamber ; ip, inner 

 pore ; Im, longitudinal muscle band ; m, margin ; 2 m, secondary 

 mesenteries ; o, mouth ; op, outer pore ; ov, ovary ; ov', loose ovum ; 

 pbm, parieto-basilar muscle ; pm, primary mesenteries ; ipr, peristome ; 

 rm, radial or transverse muscle fibres ; si, siphonoglyph ; sm, sphincter 

 muscle ; sp, spicules ; st, stomodasum or oesophagus : t, tentacle ; 

 tp, tentacle pore. 



EXCHANGES WANTED. 



Literature upon the Foraminifera, especially " Challenger " 

 Report, &c. Exchange or Cash. J. G. care of the Editor. 



Literature upon the Hydrozoa and the Annelida ; well preserved 

 fossils (named) ; foreign echinoderms and crustaceans, also centipedes 

 and scorpions in spirit. Exchange in micro, slides, zoological 

 specimens, &c. Apply to the Editor. 



Handbook to the Channel Isles. We have pleasure in directing the at- 

 tention of those interested in the natural science of our islands, to the revised 

 edition of Ansted & Lathom's " Channel Islands," 8vo., 476 pp., which has been 

 issued by Messrs. W. H. Allen & Co. Special Chapters are devoted to Zoology, 

 Botany, and Geology ; 40, 16, and 48 pages respectively, and all facts have been 

 brought up to date. The work is profusely illustrated, and it is due to the courtesy 

 of the publishers that we are enabled to use their block of adult Scyllarus arctus 

 upon a preceding page. The published price is 7/6, and at this we will send it post 

 free to any part of the United Kingdom. 



