BY R. VON LENDENFELD, PH.D. 1095 



obtuse angles, the straight basal ray just as long or a little longer 

 than the curved lateral rays. Gastral triradiate and quadriradiate 

 spicules mostly regular or sub-regular with straight or slightly 

 curved radii, nearly as long and thick as the tubar triradiate 

 spicules. The slightly curved apical ray a little shorter than the 

 3 facial rays. 



Colour : White, grey, or yellowish, seldom brown. 



Locality : Mediterranean (Nice, Naples, Messina, Triest, Lesina, 

 Haeckel ; Triest, Zara, Sebenico, Lesina, Cette, 0. Schmidt ; 

 Triest, Lieberkuehn) ; Red Sea, Siemens ; Indian Ocean, Ceylon, 

 Wright; Australia, St. Vincent's Gulf, Schomburgk ; Bass's 

 Straits, Wendt; Philippines, Bohol, Semper; Japan, Jeddo, 

 Gildemeister. 



15. SPECIES. SYCANDRA ARBOREA. Haeckel (1.) 

 SYCON ARBOREA. Polt^jaeff (2.) 

 Branched colonies composed of more or less cylindrical Sycon- 

 Persons. No peduncles and small frills. Colonies composed of 

 from 5 to 30 persons. Each measuring from 8-20 mm. in length 

 and from 4 to 8 mm. in diameter. Inhalent poiTS very regularly 

 disposed and surrounded by rings of sensitive cells and a 

 sphincter. They lead into spherical subdermal extensions of 

 the intercanals, which are wide and have a quadratic transverse 

 section. 



Spicules : Gastral quadriradiate spicules. The radial centripetal 

 ray pointing towards the Osculum and also curved in that 

 direction, pointed, conic 0-04— 0-06 exceptionally 0-08 x 0-008 

 (Haeckel), 0*08 x 0-008 my measurements. The two aboral rays 

 paired and straight, the other longitudinal and curved, concave 

 towards the gastral cavity. All of equal size, 0-037—0-04 x 

 0-006. Parenchymal Triradiates sagittaL Lateral rays 0-06 —0-1 

 X 0-005—0-006. The unpaired ray in the proximal part of the 

 ciliated tubes shorter than the others 0-05 x 0-004 ; in the distal 

 part longer, 0-12 x 0-007 mm. Dermal acerates short and stout. 



(1.) E. Haeckel. L.c, Seite 331 ; Taf. LIIL, figs. la-It ; Taf. LVIII. 

 fig- 7. 

 (2.) N. Polejaeff. L.c. Part XXIV., p 40. 



