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PROCEEDINGS OF TEE NATIONAL MUSEUM. 



VOL. 50. 



The comparison of maxillary length is as follows : 



The range of other measurements are here appended for compar- 

 ison with other species. 



Despite the distinctness of the two species, the most sharply defining 

 difference is that of color, for all the above measurements are found 

 to overlap on the examination of larger series. Taking the extremes 

 of a himdred specimens of G. attenuatus, the longest head lengths are 

 found to exceed the shortest head lengths of G. maculatus. The 

 latter, however, has a more regular and more clearly defined color 

 pattern, with larger spots, so that, with the exception of a few inter- 

 mediate individuals, the two may bo easily distinguished. Regan ^ 

 used the position of the ventrals to differentiate these forms. (See 

 third table above.) It is apparent that these plainly distinct species 

 are yet not distinctly separated by any one character. The other 

 species of the genus have not been exammed, but it is evident that 

 caution is necessary in dealing with them, in view of the wide 

 variation. 



9. HAPLOCmXON ZEBRA Jenyns. 



Numerous specimens from Mayne Harbor, Latitude Cove, and 

 Port Otway, Pafeagonia. 



10. HAPLOCHITON TAENIATUS Jenyns. 



A single large specimen of this species from Island Harbor, Pata- 

 gonia, 180 mm. in total length, presents the following differences 

 from Haplochiton zebra: Depth less, 6^- in body length to base of 

 caudal; eye very much smaller, 6| in head; depth of caudal peduncle 



> Proc. Zool. Soc. London, 1905, vol. 2, April 5, 1906. 



