1884.] Zoölogy. 93 
tendency to entangle with those of other eggs so as to form 
bunches or strings, Mr. Ryder suggests that they may be the 
means by which the parent fish is enabled to suspend its ova to 
the stems or leaves of plants. The ovary of a full-grown Men- 
idia does not contain more than 300 eggs, while the silver-gar, 
the eggs of which have filaments scattered over the whole surface, 
contains 800 to 1000 ova. He notices that the number of ova 
produced by fishes is in some way proportioned to their chances 
of survival, and that in this respect species with thread-bearing 
eggs hold an intermediate position. The same naturalist has 
an interesting notice of the breeding habits and development ot 
Amiurus albidus, as exhibited by examples in confinement. The 
eggs were about 2000 in number, and formed a mass about eight 
inches long, four inches wide and one-half to three-fourths of an 
inch thick. Their surfaces were adherent but not gelatinous, so 
that intervening spaces remained between them for the passage of 
water. The female took no further notice of the eggs after de- 
positing them, but the male watched carefully over them until 
the young had escaped from the egg-membranes, hovering over 
the mass and forcing fresh water through it by the rapid vibration 
of anal, pectoral and ventral fins. All of those left in his charge 
came out, while an attempt to hatch a portion of them artificially 
was less successful. The water-space in the egg was from the 
first filled with a great number of free corpuscles, a character not 
before met with (so far as Mr. Ryder is aware) in any other Tele- - 
Ostean egg. From the sixth to the eighth day the young were 
hatched, and on the fifteenth would feed. The parent fishes 
would often take into their mouths pieces of the liver thrown to 
the young, together with the young that were hanging to them, 
but it was observed that the young fishes were invariably ejected 
uninjured, An elaborate and richly illustrated memoir of a hun- 
red pages, on the brain of the lamprey eel, by F. Ahlborn, ap- 
pears in the Zeitschrift fiir Wissens. Zoologie for Nov. 6. It treats 
not only of the morphology, but also of the cellular structure. 
| Nature records the factthat Mr. Morton states that Ceratodus forsteri 
in Mary’s river, Queenland, from June to August goes in pairs, 
that they make slight indentations in the muddy bottom in from 
Six to ten feet of water, in which the spawn is deposited; the 
male and female fish remain near the spawn, and are not then 
easily disturbed. They frequent the same place every year, and 
the spawn is like that of frogs. Mr. Morton has taken it and 
hatched it in a tub of water, keeping the young alive for some 
weeks, In his paper on the oviducts of the smelt, in the Pro- 
ceedings of the Zodlogical Society, Professor Huxley, after stating 
that, as is well known, Lepidosteus presents an example of a Ganoid 
with oviducts like those of the higher Teleostei ; in the smelt, on 
the other hand, “ we have a Teleostean with oviducts like those 
of the ordinary Ganoidei.” He concludes that “there are no two 
