Mitochondrial Morphology

single-peaked, tuned receptor. After allowing for the above errors, I interpret Hillman's response as a claim that my hierarchical ordering of the tuned receptor as one part of traditional color theory was inappropriate and misleading. Indeed, Hillman says that: "The essence of the PalmerYoung paradigm . . . has nothing to do [italics mine] with the shape or narrowness of these curves." This assertion is only intelligible to me (although not necessarily correct) if the word "paradigm" in the preceding quotation is read as Hillman's "classical color vision paradigm" and not as the tunedreceptor paradigm actually described by me. The real issue would have been more clearly defined had Hillman simply made this claim more directly and then proceeded to document it. Unfortunately, Hillman's claim is not supported by any documentation from the extensive literature on color vision but is instead buttressed solely by Hillman's comment "that [he knows] of no claim to the contrary in the literature." This claim and its consensual validation are quite extraordinary: My review incorporated explicit quotations from Palmer and Thomas Young which, ab initio, described the tuning of the receptor spectral sensitivity function as well as a quotation froml MacNichol which is representative of current thinking on this problem. These quotations were intended to be representative rather than exhaustive; however, it would not be difficult for me to present the readers of Science with many more "claims to the contrary." But the quotations in the original article were already incompatible with the phrase: "nothing to do." Hillman's difficulty in accurately reading what I said seems to extend to what Palmer and Young said as well; Hillman does not distinguish between "shape" and "narrowness" (in the bandwidth sense). As I said in my review, a tuned receptor ". . . is maximally sensitive to a given wavelength and progressively less sensitive to other wavelengths" (1, p. 269). The narrowness (in the bandwidth sense) is not a part of this definition, nor was it a part of Palmer's and Young's descriptions. It has been necessary to deal with these issues at length because they do seem to represent views that now have some currency. In my view, it would be much better if we examine the new data, recognize that they do differ from