ZOOLOGY. 627 



veloped. In other words, the lateral line is a tactual organ specialized 

 to the same extent as those organs in certain deep-sea fishes which 

 give light. The anatomical characteristics of the lateral line are A^ery 

 diversified, but in all cases there is a similar adaptation for the per- 

 ception of sensations, and the apjiaratus is more or less protected by 

 the integuments; it is for the purpose of communicating with the seu- 

 sorium through the intervention of the lateral nerve. {Revue Bcien- 

 tijique, t. XXXIV, pp. 407-470.) 



Hermaphroditism of Fishes. — It has long been known that hermaphro- 

 ditism occurs in a number of fishes, and in some of them it is so general 

 as to almost constitute the normal form. The subject has lately been 

 reinvestigated by Max Weber. He has re-examined especially the well- 

 known cases of hermaphroditism of the sea perches of the Mediterra- 

 nean, of the genus Sernimis, and also of certain Sparids. The greatest 

 number of species in which hermaphroditism is manifested are Physo- 

 clists or Acanthopterygians ; only three phystomous fishes (the carp, the 

 herring, and the pike) have yielded hermaphrodites. Besides the three 

 species of Serranus and one of Sparus, hermaphroditism has been de- 

 tected more or less frequently in various species related to Sparus. The 

 family of Sparids, indeed, furnishes no less than six species subject to 

 hermaphroditism. These are (1) Sparus aurata, (2) Pagellus mormy- 

 rvs, (3) Sargus a^mularis, (4) Sargus Salviani, (5) Charax puntazzo, and 

 (6) Box salpa. 



In the family of Scombrids, hermaphroditism has been observed in the 

 common mackerel {Scomber scombrus) ; in the Percids, in the river perch ; 

 and in the Labrids in Lahrus mixtus. One species of Ophidiids, no less 

 than three species of the family of Gadids, and one of the Soleids have 

 also yielded hermaphroditic individuals: of the Ophidiids, the OpMdium 

 barhatum : of the Gadids, the common cod, the whiting, and the fresh- 

 water burbot or cusk; and of the Soleids the common sole. It is espe- 

 cially the characteristics of hermaphroditism in the ])erch and codfish 

 that Mr. Weber has studied, and he has sought to learn the causation 

 of the phenomenon. The result, he contends, arises from the primordial 

 sexual indifference of the materials out of which are, in time, developed 

 the genital glands. At the moment of sexual specialization, a portion 

 of the elements of which these embryonic materials are constituted 

 develop toward the male sex, while the other portion undergoes succes- 

 sive modifications which tend to the female sex, and from these diverg- 

 ing tendencies arises without doubt the appearance of true hermaphro- 

 ditism. It is recalled that hermaphroditism is most common in fishes 

 and becomes rarer in the higher vertebrates in which sexual differenti- 

 ation has become more decided. 



The species studied by Dr. Weber are all common European fishes. 

 Hermaphrodites have likewise been found in extra-European fishes, es- 

 l)ecially among the Serranime and the Lutjanina?. {Nederland. Tijdschr, 

 JDierMmde^ l, p. 84; Revue Seientijique, t. xxxiv, pi). 370, 377.) 



