In regard to the statistics of the other metals mentioned in the Census Report, it may be said, with truth, that they are very defective. No mention is made of gold, silver, or mercury, the value of the first-named of which produced in this country is nearly double that of all the other metals. Under zinc, there is no mention made of New Jersey, the great zinc-producing State. The yield of lead in the Mississippi Valley is put down at considerably less than its real amount. But the most important remark to be made, in this connection, is in reference to the mode of reporting the results adopted by Mr. Kennedy. Instead of giving the amount of _metal_ produced, the number of tuns of _ore_ is stated, and no clue given to the yield of the ore. This is something as an assessor’s report would be, which should give the valuation of the individuals he might be called on to appraise, in _pieces of money_, leaving it uncertain whether five cent or twenty dollar pieces were intended. The table given by Mr. Kennedy does not state what amounts of each metal are produced; and, if we attempt to arrive at them by examining the columns of values, it is found to be impossible to decide whether these values are those of the ore as mined before being smelted, or of the metals produced from them. In short, the whole matter is left in such obscurity, that it is much to be wished that the table could be expunged from the Report, as it can only serve to mislead and confuse those who resort to Government documents for information in regard to our metallic and mineral productions. [1] In point of fact, the amount of bar iron made in the bloomery furnaces direct from the ore is growing less every year, and must be now reduced to a very small figure. Dr. Cooper remarked that, since the publication of his paper on Californian Mollusca, read before the Academy November 3d, 1862, (see Proceedings, vol. II, p. 202) he finds the generic name STRATEGUS preoccupied, and he now proposes, in its place, the name NAVARCHUS. Professor Whitney exhibited a magnificent specimen of auriferous quartz, in which the gold was associated with _Mispickel_, (Arsenical Pyrites.) The weight of the mass was about five pounds, and the value of the gold estimated at $1,500. It was obtained from the celebrated “Fellows Lode,” on the Middle Yuba, in Sierra County. It is stated, on what is believed to be reliable authority, that from $200,000 to $250,000 has been taken from an excavation on the lode only ten feet long and four feet wide, by crushing in hand-mortars. The occurrence of gold in connection with mispickel, in the California mines, seems to be rare, at least in the southern counties. In the specimen presented, the gold formed a coherent, sponge-like mass, when the mispickel was dissolved.