224 MR. IX. KIRKPATRICK OX THE TORIFERA [Mar. 6, 



" the specimen covered the submerged suii'ace of a lai-ge stone to 

 tlie extent of over a square foot in area ; the crust was closely 

 adherent and very thin." 



The thickness of the crust is 2 mm. There are no oscules on 

 the fragments of the specimen. The surface is level and provided 

 with tufts of spicules "16 mm. in height, formed by the ends of 

 the main fibres. 



The skeleton is formed of main longitudinal fibres about 6 

 spicules thick ; at varying levels these fibres give oft' transverse 

 secondaiy fibres 2-3 spicules thipk, which meet the extremities of 

 those from other main fibres ; in parts where the main fibres are 

 closer together the secondary bundles reach aci-oss from one main 

 fibre to iinother, and the secondary bundles are thicker. 



Thei-e are ti-aces of a basal spongin-lamella in the form of bi-oken 

 scale like fragments; but the spongin-fibres are reduced to mere 

 cushions, into which the ends of the basal oxeas are immersed. 



Spicules. — The megascleres are smooth curved oxeas 214 x 18-5^j, 

 with subtornote ends ; fiequently with a centi'al knob. 



Micro-strongyles, scattered about in the tissues, are identical 

 with those of the gemmules, and in all pi'obability have belonged 

 to those bodies. 



The gemmules are spherical, 380-425 /x in diameter, with one, 

 two, or three pore-tubes, each rising about 1 8 /i beyond the sur- 

 face. The position of the pore-tubes varies, and when there are 

 several they may be scattered over the circumference or close 

 together. In one instance a pore-tube is thick- walled, closed at 

 the end, and bent over. 



The yejnmule-spicules are micro-strongyles, airanged tangentially 

 in one or two layers on the chitinous capsule. When there is 

 only one layer, a tessellated or parquet-like pattei'n is discernible, 

 each tessella being made up of a pai'allel row of 4-6 micro- 

 strongyles, and fitting in with neighbouiing tesselkv at varying 

 angles. When the layer is double it is difiicult to make out any 

 pattern ; here and thei-e the spined ends of the spicules project 

 above the general level. 



The strongyles are of two kinds : in one, 70 x 12 /i, the sjjicule 

 is slightly curved, of nearly uniform diameter, spined all over 

 with short blunt vertical spines, but less so in the centre ; in the 

 other, which is 65 x 16 fi, the centre is nearly smooth, swollen, and 

 barrel -shaped, and tapering to the spined ends. 



Affinities. — The gemmule-spicules somewhat resemble those of 

 Spongilla sumatrana Weber, of which species Weltner describes 

 two African varieties ; in all these there are short spined micro- 

 strongyles, but there are no flesh-spicules in the new species, and 

 the megascleres ai'e smooth, whereas in S. sumatrana and its 

 va^rieties there are flesh-spicules and the megascleres are spined. 

 Spongilla permixta Weltner fi-om German East Africa, of which 

 species only the gemmules are known, has sj^ined microsti'ongyles 

 for its gemmule-spicules, but these are much moi'C slendei-, being 

 only 3 fj. in diameter, and with recurved spines. 



In >S. biseriata Weltner the oxeas of the skeletal framewoi'k are 



