370 SUPPLEMENTARY NOTES 



Botryllus rubens, Alder and Hancock. 



"General envelope thin and transparent, dull brown, with 

 numerous opaque yellow granules. Individuals forming circles, 

 or stars, of from four to fifteen, generally averaging seven or 

 eight ; their colour is various shades of red, from reddish-yellow 

 to dark brick-red : there is usually a circle of dark red round the 

 branchial aperture, and at a little distance from it, and a streak 

 of the same down the centre of the thorax ; the remainder of the 

 body is pale red or yellowish, thickly sprinkled with opaque 

 yellowish-white spots. General aperture of each system, rather 

 small. The stars are smaller, and not so closely set as in the last 

 species. 



" On the under side of stones between tide-marks, Cullercoats, 

 frequent. 



" We have occasionally seen the central red line of the body so 

 much diminished that it leaves little more than a spot, and in 

 that case the species might be taken for the last ; but it may 

 always be known from it by the thinness of the general envelope, 

 and the more variegated reddish colour of the inclosed animals." 

 — Ald. Cat. p. 110. 



B. virescens, Alder and Hancock. 



" General envelope moderately thick, olive-brown coloured, 

 sprinkled with yellow spots. Individuals forming circles of from 

 six to twelve. Colour grass-green, varying to greenish yellow, 

 and occasionally to pale grey ; the colour is in most cases con- 

 fined to the lower part of the animal, the upper portion being so 

 nearly the colour of the envelope as to be with difficulty dis- 

 tinguished from it. Branchial apertures large, with a faint 

 red margin ; the tentacular filaments very conspicuous within 

 them, of a pale yellowish colour. When magnified, the colour 

 of the body is shown to be formed of a copious sprinkling 

 of opaque spots, mostly confined, as before stated, to the lower 

 part of the animal, but sometimes extending round the disc. 

 Common central apertures largish, margined with red. Not 

 uncommon on the under side of stones within tide-marks, along 

 with the last. The arrangement of the markings distinguishes it 

 from the B, smaragdus of Milne-Edwards." — Ald. Cat. p. 111. 



