ZOOLOGY. 627 



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

 to the same extent as those oi-gans in certain ilecp-sea fishes which 

 give light. The anatomical characteristics of the lateral line are very 

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

 cwption of sensations, and the ai)paratus is more or less protected by 

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

 sorium through the intervention of the lateral nerve. (Revue Scien- 

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



MerwaphrodiUsm 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 nonnal form. The subject has lately been 

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

 known cases of hermai)hroditism of the sea perches of the Mediterra- 

 nean, of the genus AStrra«».v, and also of certain Sparids. The greatest 

 number of species in which hermaphroditism is manifested are Physo- 

 clists or Acanthopterygians ; only three i)hystomous fishes (the carp, the 

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

 species of Serranus and one of iSpurus, 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) PageUus mormy- 

 rvs, (3) l^argiis annularis, (4) Sargus Salviani, (5) Charax puntaszo, and 

 (G) Box salpa. 



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

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

 and in the Labrids in Labrus mixtus. One species of Ophidiids, ]io less 

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

 also yielded hermaphroditic individuals: of the Ophidiids, the Ophidium 

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

 water burbot or cusk; and of the Soleids the c^mujon sole. It is espe- 

 cially the characteristics of herma])hroditism in the ])eich and codfish 

 that Mr. Weber has studied, iind 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 otJjer portion undergoes succes- 

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

 ing tendencies arises without doubt the appearance of true berma])hro- 

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

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

 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- 

 j)ecially among the Serraniiia^ and the Lutjaninoe. {Ncdoiand. Tijdsclir, 

 DierJiUnde, l, p. 84; Revue Scientijiquc, t. xxxiv, pj). 370, 377.) 



