338 I'h^ Philippine Journal of Science wis 



is unusual for Eudendnum. The branching is very irregular. 

 The hydrocaulus originates as a hydranth bud on the hydro- 

 rhiza. As this hydranth develops, the pedicel is produced be- 

 tween it and the hydrorhiza and becomes decidedly elongated. 

 In its simplest form the hydrocaulus consists of this pedicel and 

 terminal hydranth (fig. 1, a). The pedicel may remain single 

 or send off a bud, which usually appears near the distal end (fig. 

 1, b). While the bud grows and develops a pedicel of its own, 

 the original pedicel still increases in length, and a form results 

 such as is shown in fig. 1, c. Both of these pedicels may bud and 

 send off new pedicels, or, as is more commonly the case, only the 

 terminal pedicel buds, producing a form such as is seen in text 

 fig. 1, d and e. The production of pedicels along the original 

 outgrowth from the hydrorhiza usually continues until there are 

 several unbranched pedicels arising from the original hydrocaulaL 

 trunk as in fig. 1, e. This may be the permanent form of the 

 hydrocaulus, or one or more of the upper pedicels may produce 

 buds which develop into hydranths with pedicels as in fig. 1, f, g,- 



i 



6 c </ e / g -* 



Fig. 1. The branching of EuAenArium griffini. 



and h. In a closely packed colony, the lower pedicels of such 

 hydrocauli have as a rule lost their hydranths (fig. 1, h), which 

 is probably due to crowding and inability to get food, while the 

 terminal one or two hydranths, especially in a female colony, 

 are sterile and attenuated and drop off at about the time of the 

 maturing of the gonophores. The intermediate hydranths appear 

 to be normal, healthy individuals either bearing gonophores or, 

 if not, being of normal size and appearance. The degeneration 

 of the terminal hydranths may be attributable to senility since 

 they are the original and oldest hydranths of the hydrocaulus. 



The hydrocauli are so numerous and the hydranths borne by 

 them so close together that a healthy colony forms a mossy 

 growth over the entire surface of attachment, hiding the hydro- 

 rhiza and the hydrocaulus with the exception of the pedicels. 

 This gives the colony a superficial appearance more like Stylactis 

 or Tubularia than like Evdendrium. In the recumbent position 

 of its hydrocauli and in the close resemblance between its hydro- 

 cauli and the hydrorhizal elements, this species differs decidedly 



