1853.] | 431 
productis cbtusis, superficie triquetra ~ellulis magnis hexagonis favosa. Had. 
Mindanao. 
13. TriceRaTIuM Witxzst, H. et B.; loricé lateribus convexiusculis angulis 
rotundatis, superficie ut in T. concavum notata. Hab. Puget’s Sound. 
Appendiz. 
14. Lacena Wittiamsonti, H. et B.; testa bicellulosa, cellulis diversis, infe- 
riore ellipsoidea longitudinaliter costata in isthmum infundibuliformem attenuata, 
et ad cellulam superiorem glabram semi-lageneformem (vel inverse infundi- 
buliformem) ferruminata ; collo breviusculo recto, ore subampliato. Had. Min- 
danao. 
List of Diatomacee, collected by the United States Exploring Expedition under 
Capt. Wilkes, U. S. N. 
By Pror. J. W. Batter. 
Although no collection of the Diatomacee was purposely made by the Ex- 
ploring Expedition, a careful examination of various specimens of marine mud, 
&c. adhering to the alge, shells, &c., which were brought home by Capt. Wilkes, 
was rewarded by the discovery of many interesting forms, a list of which is here 
given in the order of their geographical distribution. 
Puget’s Sound, Oregon. 
DiaTOMACER. 
Actinoptychus senarius, Ehr. Grammatophora undulosa, Ehr. 
*Aulacodiscus Oreganus, H. et EB. Isthmia obliquata 
*Amphitetras Wilkesii, H. et B. Rhabdonema arcuatum, Kutz. 
Arachnoidiscus Ehrenbergii, Bailev. Surirella fastuosa, Ehr. 
*Cocconeis rhombifera, H. et B. *Triceratium Wilkesii, H. et B. 
2 oO sulcata, H. et B. Spongiolites, bc. 
Coscinodiscus oculus-iridis, Ehr. Spongiolites Agaricus, Ehr. 
OC radiatus oe Dictyocha splendens, Ehr. This is now 
66 excentricus known to be a calcareous plate from a 
Epithemia gibberula, Kutz. species of Synapta. It dissolves in 
Grammatophora angulosa, Ehr. acids, and polarizes light. 
Of stricta, 06 
San Francisco, California. 
Arachnoidiscus Ehrenbergii, Bail. 
Cocconeis scutellum, Ehr. 
Gomphonema minutissima, Ehr. 
Terra del Fuego. 
Entopyla australis, Ehr. 
Grammatophora serpentina, Ehr. 
Ge stricta G 
Rio Janetro. 
Climacosphenia australis, Kutz. Dictyocha splendens, Ehr. 
Grammatophora oceanica, Ehr. Spongiolites anchora, ¢« 
*Isthmia minima, H. et B. Both of these come from the calcareous 
particles of an Echinoderm (Synapta). 
Valparaiso. 
Stauroptera aspera, Ehr. Gallionella sulcata, Ehr. 
Cocconeis scutellum, ‘ Grammatophora hamata, Ehr. 
Actinoptychus senarius, Ehr. Dictyocha speculum, € 
