ALGA 179 



COSCINODISCUS LINEARIS, Ehr. 



Zygoceras margaritaceum. (Tab. 9, fig. 31.) 

 Gaillonella sulcata, Ehr. 

 Grammatophora oceanica, Ehr. 



* Lagena Williamsonii, Bail. & Harv. (Tab. 9, fig. 33.) 



L. testa bicellulosa; cellulis diver sis, inferiore ellipsoidea longitudinaliter 

 costata in isthmum infundibuliformem attenuata et ad cellulam supe- 

 riorem semi-lageniformem (vel inverse infundibuliformem) ferrumi- 

 nata; collo breviusculo recto ; ore subampliato. 



Hab. Found in mud, attached to a Hammer oyster, Mindanao. 



Shell, with two cells ; the upper one ellipsoidal, with longitudinal 

 ribs, connected by a narrow neck to the lower cell, which in shape 

 resembles two funnels with their larger openings placed together. 

 Aperture slightly expanded. 



We dedicate this species to Professor Williamson, of Manchester, 

 England, whose valuable memoir on the species of Lagena, may be 

 found in the Annals and Magazine of Natural History. 



Navicula elongata ? & N. Lyra, Ehr. 



PlNNULARIA DIDYMA, Ehr. 



Stauroptera aspera, Ehr. 



SURIELLA FASTUOSA, Ehr. 



Terspine musica, Ehr. ? (Tab. 9, fig. 12-13.) 



* Triceratium orientale, Bail. & Harv. (Tab. 9, fig. 9.) 



T. magnum, lateribus convexis, angulis productis obtusis, superficie tri- 

 quetra cellulis magnis hexagonis favosa. 



Hab. Mindanao ; in mud, on Hammer oysters. 



Lorica larger than in T. Favus, with the sides convex and the angles 

 much produced and rounded : the surface is reticulated, nearly as in T. 



Favus. 



CONIODICTYON SPLENDENS, Ehr. 



Spongiolites ANCHOR A, Ehr. 

 Spongiolites Agaricus, Ehr. 



