‘ 
354 H. J. Clark on Lucernaria. 
a typical affinity to the fixed hydroid generation of the Sarsia, 
Bougainvillize, Steenstrupix, etc. The simple, almost unilocular 
chymiferous system is hardly more medusoidal, as regards the 
multiplicity of its subdivisions, than in some of the Tubularians, 
such as Tubularia and Corymorpha, which are described in Pro- 
fessor Agassiz’s fourth volume of his “Contributions.” In con- 
nection with the hydroid form of Lucernaria, I would also 
mention the total absence of a veil. This might, at first thought, 
appear to furnish an argument in favor of the high relations of 
this genus; but I think it is to be deemed as one of the signs of 
its inferior connections. However, let us look at the progress 
of velar development. In the ephyra state of all Steganoph- 
thalmata, the veil is at one time greatly in the preponderance, 
when compared with the size of the whole individual; but with 
owth it gradually becomes less conspicuous, and, finally, 1 
some adult genera of this order, it remains as a mere trace 
a veil, or, as in Cyanea and some Rhizostomide, it is altogether 
obscured. Now, it is noteworthy that among the lowest of this 
order, such as Pelagia, we have a strong resemblance to the 
ephyra state, and the ephyroid, tongue-like veil is quite promb 
nent; and in Chrysaora it is hardly less so; ascending the seale, 
we find it yet more inconspicuous in Aurelia, and still more 8° 
however, is not the case, for as I know, from the study of the 
younger stages of Lucernaria, that it never passes thee os 
f 
in point of structure as the merest pigment eye-spot ° 
Gymnophthalmata. pee 
Thus, in balancing the value of the organisms of this a0 at 
we are inevitably led to the conclusion, on the one hand, that 
Lucernaria does not stand as a totality above all other Acaleph®, 
nor, on’ the other hand, does it, by any means, belong he 
em; and that much less does it affiliate exclusively with the 
into consideration, also, the eyes, which are found to be mee 
comprise not only the original ocular lappets, but also a part 
t aes, 
ise, the veil must be still farther inward, and very pro bly a ee a 
s corresponds to it, the two merging into each other. 
nally becomes a simple cavity. In Rhizostoma, Stemolph™ 
channeling is ried out than in Cyanea ; in fact, in He ™ 
little beyond Aurelia in this 
© ‘The ephyra-like appearance of Cyanea is illusory ; the lobes, about tot at : 
