220 DR. HINDE AKB MR. HOfiMES ON SPONGE-REMAINS 



Latrunculia (p). — PL XI. fig. 2.5. Spicule with toothed base, 

 an inverted lower disc-like w^liorl with dentate margins, and a 

 similar but npright summit whorl. These whorls are connected 

 so as to form a drum with constricted centre. The apex is 

 conical, terminated by a single spine. Length of spicule "034 

 mm,, width of whorls "OlS ram., thickness of shaft '006 mm. 



Pi. XI. fig. 26. Sceptrella similar to the preceding, but with 

 a tiara-like apex of three curved spines. 



Latrunculia (q). — PI. XI. fig. 27. Small sceptrella with base 

 of projecting spines, a thick inverted disc-shaped lower whorl, 

 with spined surface and margins: at the upper end a cup-shaped 

 whorl with a dome-shaped, minutely-spined apex. Length of 

 spicule "02 mm., width of lower whorl '015 mm., thickness of 

 shaft '005 mm. 



Latrunculia (r). — PL XI. fig. 28. Shaft of spicule with an 

 expanded dentate base, a median disc with apparently smooth 

 margins, summit cup-like with a semi-globate apex with blunted 

 spines. Length of spicule '036 mm., width of lower whorl '026 

 mm., of shaft '011 mm. 



Latrunculia (s). — -PL XI. fig. 29. Sceptrella with expanded 

 base of divergent spines, a short robust shaft, and at the top a 

 group of laminaj having a plume-like arrangement. Length of 

 spicule '026 mm., width of base '018 mm., thickness of shaft 

 •007 mm. 



PL XL fig. 31. Spicule of the same character as the pre- 

 ceding, but the spines of the base are larger and the laminae at 

 the apex are vertical. Length of spicule '035 mm. 



PL XI. fig. 30. Sceptrella with an expanded base of furcate, 

 claw-like spines, a short cylindrical shaft with a group of spread- 

 ing furcate spines at the summit. Length of spicule *023 mm., 

 width -016 mm., thickness of shaft -0047 mm. 



This and the two preceding forms (figs. 29, 30, 31) differ 

 from what may be considered the normal type of " sceptrella " 

 in not having a median whorl, and the spicule is reduced to an 

 expanded spined base and divergent laminae or spines at the 

 summit of a shoi't shaft. 



Latruncidia ohtusa, n. sp. — PL XL fig. 32. Sceptrella with sub- 

 cylindrical, obtusely ended shaft with two circular discoid whorls 

 in the upper half, their margins inflated. The summit of the 

 shaft is obtuse conical. The entire surface of shaft and whorls 

 set with minute spines. Length of spicule -053 mm., width of 



