200 AMERICAN JOURNAL 



Forbes, on the Patellacea, published in 1849, dividing that group 

 into two families, viz., Patellidae and Acmeadae, under which the 

 genera, so far as enumerated, are arranged the same as by Mr. 

 Dull, with the exception that Lepeta, or its allied genera, are 

 classified with the Acmeadae, instead of being raised to a separate 

 sub-order. Fam. Acmeidse is credited by Mr. Dall to Dr. Car- 

 penter, Maz. Cat., 1856. 



The first descriptions published by me were, it is true, in Eng- 

 lish, and short, intended to be merely provisional, as I expected 

 at that time to be able, from the Report of the several Survey- 

 ing 'Expeditions that had visited Polynesia, together with my 

 own researches and those of numerous other collectors, to make 

 out a list of the genera and species of Polynesian mollusca and 

 their distribution, in a few years. 



From the numerous errors discovered, especially as to locali- 

 ties, I was forced, however, to re-commence the work from the 

 foundation, and it is not yet complete, for I am working single- 

 handed and without assistance. 



As to species not being figured, I have given notice frequently, 

 and editors for me, both in Europe and the United States, that 

 the figures of Hawaiian species were reserved for a work in 

 preparation, on the "Mollusca of the Hawaiian Islands." 



