THE ANTHOZOA 



branching, the extreme basal portion of the stock generally devoid of 

 zooids and forming a stem. Zooids elongate, imbedded in coenenchyma 

 up to the stomodseal region, which is completely retractile within the 

 lower portion. Spicules mesogloeal, of various form, commonly fusiform, 

 and furnished with spines and warty projections. Genera (a). Mono- 

 morphic forms. A Icyonium, Linnaeus ; Paralcyonium, M. Edw. ; Sarakka, 

 Danielssen. (/?). Dimorphic forms. Sarcophyton, Lesson ; Lobophytum, 

 Marenzeller ; Anthomastus, Verrill ; Nannodendron, Danielssen. FAMILY 

 3. NEPHTHYIDAE. The zooids form upright colonies, consisting of a more 



ID 



1. Clavularia coerulea, Ehrb. A Clavularian colony with a membranous stolon. 

 2. Ammothea arborea, Forsk. A member of the sub- family Spongodinae. 

 3. A group of zooids of the same, magnified. 



4. Lemnalia nitula, Verrill. A member of the sub-family Siphonogorginae. 

 5. A terminal branchlet of the same, magnified. 



6. Heteroxtnia elizabethae, Roll. A colony divided vertically to show the elongate 'cavities 

 of the autozooids, 02, between the exsert portions of which are siphonozooids, sz. 



or less sterile trunk, and variously ramified branches bearing terminal 

 zooida or clusters of zooids. The tentacular region of the zooid is not 

 retractile into the gastral region, but the tentacles, when at rest, are 

 simply folded over the oral disc. The wide canals which run longi- 

 tudinally in the stem and larger branches are continuations of the 

 cavities of the principal zooids of the clusters. There are two sub- 

 families. 1. SPONGODINAE. The partitions between the stem canals 

 contain few or no spicules. Genera Nephthya, Savigny. The zooid 

 heads beset with long and large, but not projecting spicules. Spongodes, 

 Lesson. The zooid heads protected by projecting tufts of long spicules. 



