.SOME ASCIDIAN8 PROM THE ISLE OF WIGHT. 151 



The nonien triviale of taxonomy is a great boon to the investigator 

 in biology, but it becomes a burden when it is applied with random 

 pen to every little group of forms, distinguished though they may be, 

 under their particular conditions, by the constant possession of some 

 minute peculiarity. Minute and constant peculiarities are of the 

 greatest interest and importance, and nothing could be, for some time 

 to come, of higher value to the student of organic evolution than their 

 careful recognition and classification, involving also a similar record of 

 the bionomical conditions under which those peculiarities are found to 

 be manifested. 



But there is no reason why the specific name should be bestowed 

 upon these minutely isolated groups. They had much rather have a 

 nomenclature of their own within the limits of the species embracing 

 them ; and that such a nomenclature can be adopted with success is 

 sufficiently established by a perusal of Mr. Gosse's admirable monograph 

 of the British Actinians, — to go no further. 



I will conclude with an attempt, by way of illustration, to record 

 what seem to be the main outlines of variability in the species which 

 has just been discussed. 



ASCIDIA MENTULA, 0. F. MulUr. 



Var. 1. — Kubebeima. Body -walls beneath the test of a brilliant red or 

 rose-colour j tentacles (always ?) numerous (60 to 80). 



Form a. — Erecta. Area of attachment small, usually 

 posterior and basal ; infra-littoral. 



Distribution. — Off the south coast of 

 Norway ; Mediterranean, off Marseille and 

 Naples, rare in Adriatic (=A. rubescens, 

 HeUer). 



Form (3. — Depresses,. Area of attachment large, ex- 

 tending over the whole or the greater 

 part of the left side ; littoral. 



Distribution. — West coast of Scotland, 

 west and north-east coasts of Ireland 

 (=A. Bubicunda, Hancock). 



Var. 2. — Eubrotincta. Body-walls tinged with reddish flesh-colour. 



Form*. — Erecta. Attached aa described above ; infra- 

 littoral. Naples, Marseille, British seas ? 



