CLASS IV. DISCOPHORA. 
633 
THE FAVOISIA OCTONBMA. 
the British coast- 
no mouth, the nourishment being absorbed through a number of small pores scattered upon these 
organs, and communicating by minute tubes with the stomach, 
which, as usual, is situated in the peduncle. 
It would be in vain to attempt to describe the various forms 
of these creatures. We give a few engravings, representing 
some of the most characteristic ; as the Favonia octonema, with 
a nearly hemispherical body, showing a long proboscis, at the 
root of which are eight branchiferous appendages — hihabit- 
ing the South Seas : the Pelagia Lahiche^ Avith four foliaceous 
arms, and long filaments depending from the rim of the um- 
brella — also found in the South Seas ; and the Cuvieria curiso- 
clirovia, which is without a ccnti-al peduncle, yet has numerous 
long appendages hanging from its border. 
The stinging power, which is common to several groups of 
radiate animals, is possessed by many Medusae in the greatest 
perfection. Of the Oyancea capillata — a species common on 
-Professor Forbes speaks as follows : " This inhabitant of our seas is a most 
formidable creature and the terror of tender-skinned bathers. With 
its broad, tawny, festooned and scalloped disc, often a full foot, or 
even more across, it flaps its way through the yielding waters, and 
drags after it a long train of ribbon-bke arms and seemingly intermin- 
able tails, marking its course when the body is far away from us. 
Once tangled in its trailing ' hair' the unfortunate who has recklessly 
ventured across the graceful monster's path too soon writhes in prickly 
torture. Every struggle but binds the poisonous threads more firmly 
round his body, and then there is no escape ; for when the winder 
of the fatal net finds his course impeded by the terrified human 
wrestling in his coils, he, seeking no combat with the mightier biped, 
casts loose his envenomed arms and swims away. The amputated 
weapons, severed from their parent body, vent vengeance on the 
cause of their destruction, and sting as fiercely as if their original 
proprietor itself gave the word of attack." This is a large species ; 
most of the smaller ones appear to possess no urticating power, at least none capable of making 
an impression upon the human skin. 
The reproduction of the Medusae has been a subject of the most elaborate investigation. These 
animals are all unisexual, and propagate by eggs, which the female prodiices in glandular organs, 
sometimes arranged in bands or patches on the surface of the sub-umbrella, and sometimes in 
cavities at the base of the peduncle. But these ova, when excluded, produce creatures very dif- 
ferent from the parents, and it is not till the second generation that the original Medusa is repro- 
duced. This has led to the following theory, put forth by Steenstrup : " The fundamental idea 
expressed by the words ^Alternation of Generations,^ is the remarkable phenomenon of an animal 
producing an offspring which at no time resembles its parent, but which, on the other hand, 
itself brings forth a progeny which returns in its form and nature to the parent animal, so that 
the maternal animal does not meet with its resemblance in its own brood, but in its descendants 
of the second, third, or fourth degree of generation. And this always takes place in the ditFer- 
ent animals which exhibit the phenomena in a determinate generation, or with the intervention 
of a determinate number of generations. This remarkable preced.ence of one or more generations, 
whose function it is, as it were, to prepare the way for the later succeeding generation of animals 
destined to attain a higher degree of perfection, and which are developed into the form of the 
mother, and propagate the species by means of ova, can, I believe, be demonstrated in not a few 
instances in the animal kingdom." 
Forbes admits the general correctness of this theory, but considers that in regard to the Me- 
dusa it has many exceptions, and in illustration of this view states that at least four British spe- 
VoL. IT.— 80 
THE CUVIBEIA CAEISOCHEOMA. 
