1902.] SPOXGES OF THE " SKEAT EXPEDITION." 219 



Anatritenes, cladus 0"015-0*08 mm. 



The cladi when as short as O'OIS mm. are also very thick. 



Sigmata 0"011 mm. 



The skeleton of the walls of the oscular tubes consists of strands 

 of the moi-e slender protri8enes and prodisenes, oxeas being absent 

 in these parts. 



The ciliated chambers are 0*02 mm. in diametei'. In their 

 present state they have very distinct " Sollas' memljranes." 



Pulau Bidang. 



26. OiNACHYRA MALACCENSis, n. sp, (Plate XIY. fig. 2 and 

 Plate XY. fig. 5.) 



Since the description of the type species, C. harhatus SolLxs 

 (Voyage of H.M.S. ' Challenger,' vol. xxv. p. 23, pis. iii. &xxxix.), 

 four new species have been added to the genus ; v. Lendenfeld 

 when he states (Abh. Senck. Ges. xxi. p. 107, 1897) that his 

 G. voeltzkoioi from Zanzibar is the only species found since the 

 type, ovei-looks the thi-ee species described by Keller (Zeit. f . Aviss. 

 Zool. Hi. p. 336, pi. xix., 1891). 



The genus as now known contains the following species : — 



A. Pores confined to the porocalyces. 



a. Porocalyces rough with fine hispidating protrisenes. 



a. With rooting' spicules, with cortical oxeas, with projecting ridges on the 



sm-face of the porocalyces C. barhata Soil. 



b. Without the three characters mentioned as occurring in C. barbata. With 



rhabdodragmas scattered throughout the tissues. C eury stoma Keller. 



K«d Sea. 

 /3. Porocalyces without hispidatiug spicules. Microxeas throughout the tissues. 

 a. Porocalj'ces with an even surface. Sponge spherical with smooth surface. 



C. schulzei Keller. 

 Coast of Aden and Mozambique Channel. 

 h. Porocalj'ces with a network of projecting ridges. Sponge conical. 



C. trockiformis Keller. 



Red Sea, 



B. Pores not confined to the porocalyces, which latter are without hispidatiug 



spicules C. voeltzkowi Lendenfeld. 



Zanzibar. 



The present specimens agree with C. voeltzJcoivi in possessing 

 scattered pores in addition to those of the porocalyces. The surface 

 of the latter structures is raised into a network of fine ridges, but 

 lacks hispidatiug spicules. The sigmata are smaller than in any 

 hitherto described species. 



The sponge approaches a hemispherical form ; one specimen 

 having become attached laterally is almost bracket-shaped ; in the 

 othei- the curved surface occupies more than a hemisphere, while 

 the basal membrane is folded and forms a conical surface concave 

 to the exterior. 



The porocalyces are either cup-shaped or shell-shaped, in the 

 latter case as much as 3 mm. in diameter. 



The cortex is a uniform fibrous coUenchyma ; canals passing 

 through it from the scattered pores are clearly marked by the 

 abundant sigmata in their walls. The ciliated chambers are 

 small — from O'Ol 5-0-01 8 mm. in diameter, and composed of only 



