[23] Only a few specimens of the Carboniferous fossils collected by M. Rémond have ever been received, owing to circumstances connected with the present political condition of Mexico. It is hoped, however, that they are not lost, and that they may yet be recovered. Among the few specimens received is a coral, not to be distinguished from the _Lithostrotion_ (_L. mamillare_) found near Bass’s Ranch, in Shasta County, California. J. D. W. REGULAR MEETING, MARCH 19TH, 1866. President in the Chair. Twelve members present. Donations to the Cabinet: Sections of the _Sequoia gigantea_ and a roll showing the annual growth of the “Old Maid,” one of the trees in the Calaveras grove of Big Trees; from Mr. Henry Hentsch. Mr. Dall stated that Dr. Cooper had discovered, in the vicinity of Santa Cruz, _Helix redemita_, _H. Vancouverensis_, _H. Columbiana_, and _H. arrosa_; also, in the small rivulets near the town, _Margaritana falcata_, besides several univalves, and also an undetermined _Helix_, which may prove to be new. Mr. Dall also remarked that Rev. J. Rowell had obtained at Hayward’s, Alameda County, a number of specimens of _Helix Cronkhitei_, which is a new locality for that species. Mr. Dall remarked that in dissecting a specimen of _Trochiscus Norrissii_, the position of which has for some time been doubtful, sufficient evidence was obtained to decide that it did not belong with the Proboscidians, to which group it had been doubtfully referred by several naturalists. REGULAR MEETING, APRIL 2D, 1866. Mr. Stearns in the Chair. Five members present. Mr. Bloomer presented some Diatoms, from the coast of California, supposed to belong to the genera _Melissa_ and _Meridion_; they were both found growing upon calcareous sea weeds. The genus _Meridion_ has not heretofore been recorded as occurring in California. Mr. Dall presented, in the name of Dr. Cooper, the following paper: Description of a new California Helix, with notes on others already described. BY J. G. COOPER, M.D. HELIX (Arianta) SEQUOICOLA, Cooper. Sp. ch. _H. testa_ rotundata, umbilicata, spira depressa, anfr. ult. nonnunquam subangulata; anfr. vi ad vii et dimidium, perist. obliqua superne parum deflecta; labio tenui, reflexo, infra crassiore, acuta. Colore atrobrunnea, vel olivacea, zona nigra, lata, inter duabus ochraceis sita, in spira semicelata, labio albo; intus læte purpureo, zonis duabus albis. Epidermide nitente, infra polita, striis incrementis læve perspicuis, interdum tenuissime malleata, rugis spiralibus; supra punctis piliferis creberrime induta; pilis brevissimis junioris deciduis. _Animal_ schisto-colore; corpore cylindraceo rugosa, tentaculis longis, pede postice elongata, cuneata. _Testæ_ lat., major, 0.93 ad 1.20; minor 0.76 ad 0.96; alt. 0.42 ad 0.54 poll. Angl. _Hab._ Santa Cruz, California, in ligno carioso, locis humidissimis.