528 T. A. STEPHENSON 
similarity between them for any separation greater than generic 
to affect them. 
In B. alfordiand A. sulcata there is a definite base, 
there are acrorhagi, long tentacles, lax habit of body only able 
to retract with great difficulty, similar habitat, weak to 
moderate circumscribed or circumscribed - diffuse sphincter 
(Text-fig. 11, 5, Fr) (sometimes more diffuse in sulcata), 
numerous perfect mesenteries with fairly strong retractors, 
gonads on most of the older mesenteries, and the longitudinal 
musculature of the tentacles ectodermal. ‘The chief difference 
is that B. alfordi has rows of verrucae which A. sulcata 
has not, and of course lesser species-differences. But obviously 
the relation is too close for the two to be included in different 
families, which has been done hitherto. 
In B. alfordi and a Condylactis of which I have 
specimens, there is a definite base, there are verrucae, good 
tentacles, lax habit, numerous perfect mesenteries with fairly 
strong retractors, gonads on most of the older or all the 
mesenteries and ectodermal tentacular muscle. Here the 
main differences are lack of acrorhagi and a sphincter in 
the Condylactis. Between the pomts here given the 
similarity of the three genera should be clear. It is not always 
easy to distinguish them from each other if dealing with 
preserved material. 
These things being so, where is the line to be drawn between 
Actinudae and Bunodidae ? Given a series of forms—such as 
Anemonia, Condylactis, Bunodactis (incl. Actinio- 
idesand Anthopleura), Tealia—-where is the division ? 
Condylactis gives us verrucae but no acrorhagi and little 
or no sphincter; Anemonia has the acrorhagi but no 
verrucae, and a weakish circumscribed or diffuse sphincter ; 
B. alfordi has both verrucae and acrorhagi and a moderate 
sphincter, — circumscribed (its relations showing other grades) ; 
and Tealia has verrucae (and rarely acrorhagi) and strong 
circumscribed sphincter. 
The conclusion seems to be, clearly, that Bunodidae must 
be abandoned altogether. It should be noted that this does 
not impair the homogeneity of the Actiniidae, except as regards 
