252 ZOOPHYTES. 



Only a single specimen has occurred, which was in May. It afforded 

 two satisfactory drawings. 



Plate LII. Fig. 6. Medusa fimbriata. 



7. The same, under surface, enlarged. 



III. Beroe. — Later naturalists have subdivided the Medusarian race 

 into numerous parts, established from very unequal distinctions, some be- 

 ing important, some but trivial, slight, or equivocal. 



Perhaps the time has scarcely arrived for a systematic arrangement, 

 but the reader will derive much information on the subject, from the use- 

 ful and laborious work of M. Lesson, who has taken a very comprehensive 

 view of its whole details. 



§ 1. Beroe ovatus. — Plate LIV. Fig. 1. — This genus, which fre- 

 quents the Scotish seas in considerable variety, forms one principal section 

 of the Acalephse. But I have not understood that any personal injury is 

 suffered by the contact of any species. 



Like the subjects of the section we have left, they seem to be migra- 

 tory animals. Invited by the light and the heat, they rise to the surface 

 of the sea in genial weather, principally during the middle of summer and 

 the earlier part of autumn. None are seen during winter. 



The earliest which I have had, was on the 5th of February, on pass- 

 ing accidentally into a jar of sea-water during its replenishment. 



But the history of the genus is in every respect obscure. Like the 

 Medusa, the Beroe has a constant tendency to seek the surface of the 

 water. When specimens are vigorous, it is strongly demonstrated ; when 

 weak, they always remain below, from inability to sustain themselves. 



Some are beautifully phosphorescent, as may be seen on pouring them 

 along with the water, from one vessel into another. 



Many species, dwelling in our seas, approach an ovoidal form — very 

 irregular in some, and interrupted by rude appendages in others. 



