Introduction to Animal Morphology, 1 2 1 



■quadrangular rachis, with spiculigerous tentacles, and no 

 pinnae (Pavonaria) ; or on thick pinnae alone (Scytalium). 

 Funiculina and Halipterus have no pinnae ; the former has 

 dorsal zooids and eight-toothed calyces along its rod-like 

 axis ; the latter has lateral zooids with two-toothed cups. 

 Umbellularia has a long sterile axis, and the zooids, at first 

 simple, symmetrical, become grouped (20-30) in an umbrella 

 at the upper end. Pennatula and some of its allies are lumi- 

 nous, the light inhering in eight cords, consisting of vesicles 

 ■containing fat and multipolar cells {Panceri), on the outer 

 surface of the stomach of the zooids, continued in the buccal 

 membrane. 



2. Renillidoe have a kidney-shaped, parenchymatous, 

 laminar stock (a single pinnule), with the retractile zooids on 

 one side ; no solid axis. 



3. Veretillidae — axis elongated, quadrangular, having re- 

 tractile zooids on its entire surface ; its lower part bulbous, 

 naked (Lituaria), or soft ; longitudinally divided into four 

 tubes by two intersecting membranes, with a calcareous axis 

 in the lower part of the stem (Cavernularia) ; or simple, fleshy, 

 with a rudimental, membranous (Sarcobelemnon), or boat- 

 shaped axis. A primordial Australian form (Pseudogorgia 

 Godefroyi) has simple rows of polyps, each on a warty pro- 

 jection of the polypieroid, and no trace of an inner, horny, or 

 calcareous axis, but a broad, single, central canal, a pro- 

 longation of the combined somatic cavities. There are two 

 long, slender, and six short, thick mesenteric filaments. This 

 is a passage form to Briareaceae. 



Possibly the club-shaped Kophobelemnon, with thin cal- 

 careous axis, and no pinnules, should be the type of a separate 

 family linking Veretillidae to the true sea-pens. 



Order 4. Gorgonacese — rooted ; usually branched 

 colonies with minutely-ridged, flexible sclerobase ; often 

 with characteristic enderonic spicules (dermosclerites) ; 

 thecse often operculate. 



Three families are included: — i. Primnoidas — coenen- 

 chyma, with scaly sclerites, and club-like zooid-bearing 

 papillae (Primnoa) ; or spinose, with boat-shaped spicules and 



