CLASS IV. DISCOPIIORA. 



633 



THE FAVONIA OCTONEMA. 



no month, the nourishment being absorbed through a number of small pores scattered upon these 



organs, and communicating by minute tnbes 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, reprcsentino- 

 some of the most characteristic; as the Fuvonia octo7iema, with 

 a nearly hemispherical body, showing a long proboscis, at the 

 root of vi'hich are eight branchiferous appendages — iidiabit- 

 ing the South Seas : the Pclagia Labiche, vi^ith four foliaceous 

 arms, and long filaments depending from the rim of the um- 

 brella — also found in the South Seas; and the Cxtvicria curiso- 

 cJiroma, which is without a central peduncle, yet has numerous 

 long appendages hanging from its border. 



The stinging power, v/hich is common to several groups of 

 radiate animals, is possessed by many Medusae in the greatest 

 perfection. Of the Cyancea capillata — a species common on 

 the British coast — 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 ?,nd 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-like arms and seemingly intermin- 

 able tails, marking its course when tlie 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 urtieating 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 produces 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 tlie 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 differ- 

 ent animals which exhibit the phenomena in a determinate generation, or with the intervention 

 of a determinate number of generations. This remarkable precedence 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 hiffhcr decree 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 m not a tew 

 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. II.— 80 



THE CUVIERIA CABISOCHEOMA. 



