OBSERVATIONS AND CORRESPONDENCE. 



Spring-time in the Waters, 

 notes at the brighton aquarium. 



The sudden outburst of animal life in the tanks of large marine 

 aquaria is very remarkable at this season of the year. During the 

 winter the environment is dark, dull, and void of life, and the fishes are 

 languid and without lustre. A few warm sunny days pass and a 

 great change is visible. It seems really as if there were a spring-time 

 in the waters, for the rocks and sea-weeds now teem with myriad 

 forms of life. Numberless specks of filmy substances adhere to the 

 rocks, the thick glass fronts of the tanks, and the stones and sea- 

 weeds placed in them. 



The colours of the anemones brighten and deepen, and they 

 appear to expand with greater freedom. That small, but beautiful 

 species, the Daisy anemone {Actinia bellis), covers the tufa-rocks in 

 thick profusion. The long, slender stems and swollen calices of the 

 young forms now recall their budding namesakes of the meadows, and 

 the more expanded crowns of the older, shorter, and thicker specimens 

 resemble the full-blown flower. Delicate whorls of young serpulae 

 make their appearance, and the crimson-tipped plumes of innumer- 

 able Sabella wave from the mouths of their tubular dwellings, almost 

 hidden in masses of flocculent confervae, no longer of pallid hue but 

 of a fresh green colour. Many beautiful young colonies of rufous, 

 gray and purple compound ascidians of the cluster family (Botryllidae) 

 rapidly develop in their accustomed haunts. The violet species (B. 

 violaceus) may be seen, as usual, growing on stones at the bottom of 

 the tanks. One British species of this family [Botvylloides fulgnrale) 

 occurs at a depth of 530 fathoms between the Faroe Islands and the 

 Scottish Coast. ^ 



Sponges, like fungi, grow again and again in the same locality. 

 For many seasons a sponge has appeared every spring time in a certain 

 tank in the Aquarium. It develops and grows on the same rocky 

 exposure year after year, splits into separate masses and falls away, 

 leaving no apparent trace behind. When spring returns another 

 sponge appears on that identical spot to go through similar processes 

 of rapid growth, fission, and decay. 



The first tank in the Brighton Aquarium, a very deep and light 

 one, now presents a charming picture. The rocks at the sides are 

 dotted, here and there, with filmy white juvenile Ascidia. Branches 

 fixed to the floor are covered with compound forms. On one there is 

 a purple star-like colony of Botvylhis, and below that the young of a 

 cream-coloured fluffy species of a solitary ascidian have settled 

 down to pass their brief existence. On another, an encrusting 

 compound form of the Didemnidae may be recognised. Broad leaved 



iW. A. Herdman, The Tunicata of the "Challenger Expedition," Part II., 

 Ascidea; Compositae, p. 53. 



