53 



chors, which have no parallel in all the class of Acalephte. But there 

 are parts of the Lucernarian organism which are of a lower grade 

 than those of similar nature among the other Acalephce. I refer, in 

 the first place, to the hydra-like form of Lucernaria, and its compar- 

 ativety stiff and hydroidal tentacles, evidently indicating a typical 

 affinity to the fixed hydroid generation of the Sarsia?, Bougainvillise, 

 SteenstrupifE, etc. The simple, almost unilocular chymiferous system 

 is hardly less medusoidal, as regards the multiplicity of its subdi- 

 visions, than in some of the Tubularians, such as Tubularia and 

 Corymorpha, which are described in Professor Agassiz's fourth vol- 

 ume of his " Contributions." In connection 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 epliyra 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 growth it 

 gradually becomes less conspicuous, and, finally, in some adult genera 

 of this order, it remains as a mere trace of a veil, or, as in Cyanea and 

 some Rhizostomidae, 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 prominent ; and in Chrysaora it is hardly less so ; 

 ascending the scale, we find it yet more inconspicuous in Aurelia, and 

 still more so in Cassiopete ; and, finally, altogether absent in Cyanea, 

 the highest, in my opinion, of all the Steganophthalmata. Now, one 

 might suppose Lucernaria, in respect to the veil, to be in the same 

 category with Cyanea, which has resorbed its veil ; this, however, is 

 not the case, for, as I know, from the study of the younger stages of 

 Lucernaria, that it never passes through the veiled phase, it falls 

 short in its development as regards this particular feature of Acale- 

 phan morphology. We must take into consideration, also, the eyes, 

 which are found to be as low in point of structure as the merest pig- 

 ment eye-spot of the Gymnophthalmata. 



Thus, in balancing the value of the organisms of this animal, we 

 are inevitably led to the conclusion, on the one hand, that Lucerna- 

 ria does not stand as a totality above all other Acalephse, nor, on the 

 other hand, does it, by any means, belong below them ; and that much 

 less does it affiliate exclusively with the Gymnophthalmata. The 

 only relation that it possibly can be considered under is that of a cor- 

 relation to both types of AcalepJioi, — viz., to the Gymnophthalmata, 

 including the SiphonophorEe, and to the Steganophthalmata ; but yet 

 not as a graduated connecting link, which would seem to show that 



