56 
axonosts. As therefore the first axonost of the anal fin 
supports two baseosts completely and another partially, it 
follows that it has been formed of at least 3 axonosts fused 
together; but, as before remarked, we have no direct 
evidence of this.t The first baseost is situated in a de- 
pression and the succeeding two on an elevation on the 
postero-ventral surface of the first axonost, whilst the 
second axonost is closely opposed for its whole length to 
the same surface. The axonosts 3 to 7 fit by their tips 
into a posterior longitudinal furrow borne on the first. 
It is obvious that, as the first axonost is situated between 
vertebree 13 and 14 and axonost 7 les in front of the 
haemal spine of the latter vertebra, axonosts 1 to 7 and fin 
rays 1 to 8 are situated in a space bounded morphologi- 
cally by two adjacent vertebre. As previously men- 
tioned, in only one other part of the body are as many as 
4 axonosts found in a corresponding position. 
The posterior extremity of the anal fin presents no 
features of special interest except that the last fin ray 
articulates with the last axonost without the intervention 
of a baseost. 
The mechanism of the fin ray has now to be described 
(see fig. 16). Each ray consists of two longitudinal 
distally segmented pieces (F'.R. a, 6) held together by a 
transverse ligament (/’.R. c).. Proximally these two 
pieces diverge and embrace the baseost (Bs.), and also to 
a limited extent the axonost (Az.). The articular surfaces 
bear pads of a peculiar kind of soft cartilage (JZ.C.). Hach 
half of the fin ray is connected with the baseost by a stout 
ligament (7.22. d). Now the only connection between the 
+ Whatever doubts may arise on this point will be settled by a reference 
to the condition in Solea, as described by Cunningham; and in Rhombus, 
as described by Kyle. 
