22 



MISS RUTH M. HARRISON ON NEW ALCYONARIA 



genera. In Chironephthya there are generally two to four spicules arranged " en 

 chevron " in the points of the antkocodiae, while in Siphonogorgia the spicules of the 

 points are arranged irregularly or practically straight and not inclined towards one 

 another. But even among the CMronevhthyoe there are considerable variations in the 

 armature of the polyps. The three original 'Challenger' specimens are so similar in 

 form and general spiculation that Prof. Hickson suggests that "it will be found in the 

 future that it is not advisable to recognize in them more than one species." Having 

 had an opportunity of examining the actual specimens I doubt this The polyp of 



Fig. 3. 



Fig. 4. 



Fig. 3. — A transverse section through a branch of Siphonogorgia rotunda. 



Fig. 4. — A transverse section through a branch of Chironephthya pendula. 



('. dipsacea is entirely different from that of the other two ; and although I admit that 

 C. crassa and C. scoparia are probably the same species, I think C. dipsacea should be 

 kept distinct, or at any rate notified as a distinct variation. I append three camera 

 drawings (PI. 6. figs. 61, 62, 63) of the polyps of the ' Challenger ' specimens, which have 

 not been figured before. It will be seen that the polyp of C. dipsacea is not only smaller 

 but is much more like a Siphonogorgia. Another very characteristic feature of 

 Chironephthya is the presence in the partition-walls of a large number of minute 

 elongate spicules averaging about 0"25x0'02 mm., pointed at both ends and beset with 

 short spikes, and generally tinged with a paler shade of the characteristic colour of the 

 colony. Por example, in the three specimens of C. variabilis these spicules are orange, 

 red, and pink respectively. These characters seem to me to express in a decisive manner 

 what Wright aud Studer originally meant when they said that " the habit of the colony 

 was more suggestive of Nephthya," and are of far more importance than such characters 

 as the retractility of the polyps or the arrangement of the spicules of the anthocodia". 

 As a matter of fact, the polyps of Chironephthya are seldom retractile, and there arc 



