146 BULLETIN OF THE 
both intermediate and primary, although the tentacular bulbs at the ends of the 
radial tubes are larger than the remainder. This predominance in size they 
always retain. Fig. 1, Plate L, represents a young Lizzia, intermediate in 
form between that figured by Forbes and the adult L. grata as given by Mr. 
Agassiz. The addition of two more tentacles to the primary clusters completes 
the number five and. gives for the adult, as far as followed by any observer, 
thirty-two tentacles in all. "There appears, however, no satisfactory evidence 
that this is the maximum number possessed by the adult, and possibly the in- 
termediate clusters likewise inerease to five tentacles instead of three, which 
would give it a resemblance to the genus Rathkea of Haeckel. 
Lizzia passes through a Dysmorphosa and Margelliwm stage, and has the 
power of germination throughout them both. It seems, therefore, hardly 
proper as yet to form new genera, as Haeckel has done, on what are surely 
embryonic features, The genus Rathkea of Haeckel, or Oceania Blumenbachit 
of Rathke, in the description and figures of the latter, has ejght chymiferous 
tubes. I do not feel justified in considering with Haeckel that four of these 
tubes are folds of the bell or muscular fibres. There is one feature found only 
in more advanced stages, which seems to be wanting in all the immature con- 
ditions of the Lizeia, Four small bundles of oral knobs are formed on the 
under side of the lips near the bifurcation of the oral tentacles. These make 
their appearance at the same time that the second tentacle in the intermediate 
clusters develops. Mr. Agassiz has given a good figure of them in the adult 
proboscis (N. Amer. Acal., p. 162). 
The specimens of Lizzia, with buds in all sizes, which I have studied, were 
taken abundantly in tide eddies in Laboratory Cove, at Newport, R. I. The 
development of the egg is unknown. At the: junction of each of the radial 
tubes with the stomach, in older specimens, clusters of small ovarian-like cells 
were observed, which resembled undeveloped ova, but I was unable to defi- 
nitely form an opinion as to their exact character. 
Mabella gracilis, n. g. & s. 
Plate VI. Figs. 2, 3. 
A single specimen of a very interesting jelly-fish was taken near the close of 
the month of July. This medusa is of a genus as yet undescribed, and re- 
sembles Dysmorphosa very closely, with the exception (?) that it has eight radial 
chymiferous tubes. Gemmation from the proboscis similar to that which has 
been described in Liza, combined with the last-mentioned characteristic, 
makes it a most interesting and exceptionable jelly-fish. The bell has the 
shape of a very convex watch-crystal, the height of which is about one half its 
radius, It is transparent, colorless, and the surface is covered sparsely with 
small papilla. The chymiferous tubes are narrow, without side appendages, 
simple, and eight in number, Proboscis without a peduncle, quadrate, with. 
four undivided and non-bifurcated oral tentacles, which have their club-shaped 
