Page:Wood 1865 - The Myriapoda of North America.djvu/15

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I have never seen any Lithobii from the State of Louisiana, and therefore do not like to speak positively as to the validity of Herr Koch's species; still it seems certain that few if any of the characters which he gives are fixed and definite. The number of labial teeth, of the eyes, shades of color, &c., the examination of thousands—literally thousands—of specimens long since convinced me vary considerably,—at least in North American species. There appears to be only one character given by him which would indicate that L. transmarinus, Koch, is different from L. americanus, Newport; it is where he says: fourth chief scuta with a toothlike process, whose inner margin is reflexed (aufgeworfen). As to the number of the depressions on the posterior coxæ, they are not the same even on the two sides of the same individual. On page 39, Herr Koch gives the numbers in some five individuals. In these the one extreme is very nearly twice as great as the other. Are we, then, to create new species because of differences of 4 or 5 in the number of these depressions? Again: the only important difference between L. transmarinus and L. mordax, deducible from the description, is in the number of the ocelli. Herr Koch assigns only 24 to the latter; but Mr. Newport assigned 25—26 to L. americanus! Now, does it not seem very possible that L. transmarinus and mordax are one and the same species, which is really L. americanus of Newport?