1892.] VARIATION IN SECONDARY SEXUAL CHARACTERS. 585 



natural size, was obtained by Sir George Baden Powell in Petro- 

 paulovski harbour, Kaintscliatka, on Sept. 8, 1 891. Before describing 

 this fish as new I have satisfied myself, by a careful comparison 

 with the original description, tliat it cannot by any means be 

 referred to Ophidium ocellatum, Tilesius, which it strongly resembles 

 in general appearance. Notwithstanding the several different names 

 which have been bestowed upon it, this Ophidium ocellatum, ob- 

 tained at Petropaulovski, has not been rediscovered since its descrip- 

 tion in 181 1, and its affinities are altogether uncertain. 



3. Ou some cases of Variation in Secondary Sexual Characters, 

 statistically examined. By W. Bateson, M.A., Fellow 

 of St. John's College, Cambridge, and H. H.Brindley, 

 M.A., St. John's College, Cambridge. 



[Eeceived November 15, 1892.] 



It is a familiar fact that many insects are provided with lono-, 

 chitinous horn-like proces-es of various shapes and forms. Such 

 horns are sometimes ))resent in both sexes, but more commonly 

 they attain their chief development in the male only. Among 

 beetles the most striking examf)les are found in the Lamellicorns, 

 many of which have iiorns of great size on the liead, or on the 

 thorax, or on both. Analogous developments are seen in the great 

 mandibles of the males in some Lucanidae, of which the Stao^-beetle 

 (Lucanus cerviis) is a common representative. In the majority of 

 these forms the similar parts of the females are either not produced 

 at all or are much smaller. Now in many species having these 

 curious horns in the male sex, it has long been observed that the 

 males are not all alike in the degree to which the horns are devel- 

 oped ; but that, on the contrary, some of the males mav bear 

 massive horns of prodigious size, while other males of the same 

 species have hardly any horns at all, being in fact very like females. 

 The males with the great horns are in common parlance known as 

 "high "males, those with the rudimentary horns being " low " 

 males. A good series of figures illustrating the phenomenon is 

 given by Darwin \ and examples of such Variation in Odontolabis 

 &c. are exhibited in a show-case iu the Natural History Museum 

 at South Kensington. 



The phenomenon of great Variation in the development of horns 

 present in the males as a secondary sexual character is not peculiar 

 to beetles, though in them it perhaps reaches a climax. A similar 

 case is presented for instance by the Common Earwig {Forficula 

 auricularia), in which the terminal force[)s are iu some males no 

 larger than those of the female, while in others they are three times 

 the size. 



1 ' Descent of Man,' 1871, vol. i. pp. 363-375. 



