PISCES. 
147 
lopment of this part in Salmo salar from the first day of its 
being hatched, he concludes his paper by pointing out the nature 
; of the several elements constituting the end of the vertebral 
j column. 
Lereboullet, a. Recherches sur les monstruosites du Brochet 
t observees dans Pceuf et sur leur mode de production. Ann. 
Sc. Nat. 1864, i. February to May (pp. 113-193, 257-320). 
Monstrosities of the embryons of the Pike are of common 
occurrence ; they are either double, produced by a superabun- 
dance of the plastic embryonic matter, or simple, one individual 
being partially or wholly defective. The author has proved, by 
a long series of experiments, that the disposition to monstrosity 
is inherent in the ovum, and that it is entirely independent of 
' external influences; however, it would appear that the latter, 
/ whether physical or mechanical, may sometimes be the cause of 
an arrest of development of the whole individual or of some 
j part of it. 
Halbertsma, H. j. Normaal en abnormaal Hermaphroditis- 
mus by de Visschen. Versl. en Mededeel. Akad. Wet. 
Amsterd. 1864, xvi. pp. 165-178, with a plate. 
The author recapitulates the cases of hermaphroditism ob- 
served in fishes, lie distinguishes two kinds: 1. The normal 
hermaphroditism is symmetrical; that is, a testis is developed 
between the membranes of each half of the ovary, and each half 
of the primitive double embryonal gland (Kiemklier) is meta- 
morphosed into a testis and ovary. This is the case in the 
Serrani of the Mediterranean. 2. The abnormal hermaphro- 
ditism is asymmetrical, and found on one side only ; the testis 
and ovary are separate bodies, and the halves of the embryonal 
gland are never metamorphosed into testis and ovary on both 
sides of the same individual. Such hermaphrodites have been 
observed in the Carp, Cod, Perch, Melanurus (probably Oblata 
melanurd), Acipenser huso, Pike, and Gadus merlangus. — An 
hermaphroditic Perch is figured. 
McDonnell, B. On the system of the '^Lateral line^^ in 
fishes. Trans. Roy. Irish Acad. vol. xxiv. 1864 (read 1862, 
May 26, pp. 161-187, with four plates). 
The author describes and figures in this memoir the system 
of the lateral line of various British fishes [Raja, Carcharias, 
Squalus, ChimcBra, Acipenser, Pagellus, Mugil, Syngnathus, 
Acerina, Lampris, Anguilla, Platessa, Esox, Petromyzon) , and 
of Lepidosiren. He rejects VogPs view, that it is only a system 
of absorbent vessels, containing lymph, and water forced in from 
without, and Geoffroy St.-Hilaire^s opinion, who considered it 
to be related homologically or otherwise to the electrie organs. 
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