154. REPORT OF COMMISSIONER OF FISH AND FISHERIES. [448] 
into minute, oblong, ciliated larve; these soon become attached by one 
end and grow up into broad-disked young, like hydroids with long, 
slender tentacles; each of these after a time sends out stolon-like tubes 
from the base, and from these tubes buds are developed, each of which 
grows up into a “ scyphostoma,” or hydroid-furm, like the first one ; all 
these eventually become much elongated, then circular constrictions begin 
to form along the body, which grow deeper and deeper until they sepa- 
rate the body into a series of concave segments, which are held together 
by a pedicle in the middle of each, their borders at the same time be. 
coming divided into eight lobes, or four bilobed ones; in the mean time 
the long tentacles around the upper end or original disk of the “scyph- 
ostoma” gradually grow shorter and are finally entirely absorbed; then 
the first or upper disk breaks off, and finally all the rest, one after 
another, until a mere stump is left at the base; after becoming detached 
each of the disks swims about in the water, and gradually develops its 
mouth, stomach, tentacles, and other organs, and, turning right side up 
and rapidly growing larger, eventually becomes a large and complicated 
jelly-fish, like its grandparents or great-grandparents that produced 
the egg from which the original “scyphostoma” was developed. The 
stump of the hydroid produces another set of tentacles, even before the 
separation of all the segments, and grows up again into the elongated 
or “‘strobila” form, and again undergoes the same process of transverse 
division, thus producing successive crops of jelly-fishes. In these cases 
there are alternations of generations, accompanied both by budding and 
fissiparity. The young of this species in the “ephyra” stage were found 
April 17, and at several other times during April, in abundance, by 
Mr. Vinal N. Edwards. These were less than a quarter of an inch in 
diameter, and must have become free only a short time before. On 
April 30 he took young specimens from half an inch to about an inch 
in diameter. The young of various sizes, up to nearly three inches in 
diameter, were common at New Haven May 5. All these young speci- 
mens were taken in the day-time. 
In some jelly-fishes buds may even be produced upon the proboscis of 
the adult jelly-fish, which develop directly into free jelly-fishes, like the 
parent. This is the case with the Dysmorphosa Julgurans, found in these 
waters, and with Lizzia grata, found farther north. 
On the other hand there are many jelly-fishes that do not have a 
hydroid state, nor bud, noz pass through any marked metamorphosis. 
This is the case with our Pleurobrachia rhododactyla, Idyia roseola, and 
other Ctenophore. In these the young, even before hatching, become 
perfect little jelly-fishes, and swim round and round within the egg by 
means of the miniature paddles or flappers along their sides. The young 
are, nevertheless, very different from the adults in form and structure. 
It will be apparent, from the preceding remarks, that a complete 
list of free-swimming animals would necessarily include all the Aca- 
lephs of the region, but, as this would uselessly swell the list, only 
