Geology and Natural History. 251 
accidentally arias at that point, by shipping, or are really 
indigenous, cannot at present be determined. They are now cer- 
tainly well established ee of our shores. They may have 
nye verlooked hither 
4. Rapid diffusion of mgr — on the New England 
Coast ; by A. E. Verr well-known to American conchol- 
ogists that this common epee plates has become well-estab- 
lished on the New ere coast within ten or twelve years, 
appearing first on the of Maine about 1868; Dr. Dawson, 
however, states that he pars it on the shores of Nova Scotia 
at a much earlier date. wish, at present, merely to put on 
record some additional data, as to its ge rig along the 
coast. In 1873, it was collected, in gests , at Saco, Maine, by 
the U.S. Fish Commission, and was found apkilieg gly ‘at Peake’s 
L, Casco Bay. In 1872 it was ph rare at Provincetown, 
Mass., but in 1875, it was common there. In 1875, it — collected 
by the writer at Barnstable, Mass., on the shores of Cape Cod 
Bay, in large quantities. In 1879, it had become exceedingly 
abundant at Provincetown. In 1875, our parties found two speci- 
mens only, on the southern shores of Cape Cod, at Wood’s Holl, 
but in 1876 it was found to be common there, and is now very 
abundant. he first specimen found so far westward as New 
Haven was obtained by Professor 8. i Smith, during the past 
winter. Other solitary specimens have since been obtained here 
Mr. E. A. Andrews, and by Mr. J. H. Emerton. It is, at 
present, exceedingly abundant at Newport, 
5. Artific tal propagation of the Sp anish Mackerel ( Cybium 
maculatum) ; by A, E, Verrii ber 298 this highly valued fish 
habitually breeds at certain localities in Chesapeake Bay was 
recently ascertained by Mr. R. arll, of the U. 8. Fish Com- 
mission. In July, he visited the locality and made experiments 
upon its artificial propagation. He was very successful and easily 
hatched many thousands of the young fish. These, though among 
utilize this discovery next year on a large scale, and there is every 
reason to believe that this excellent fish wed se thus ee ga 
into all the waters south of. Cape Cod, in g bundan 
6. Occurrence of Ciona cowie 1 (iia eal Ages aSsiz) a 
— R. I; by A. E. Verrmu.—This ascidian, which i is one of 
