50 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 4 



Synthecium symmetricum, new species 

 Plate 12, Fig. 57 



Trophosome. — Colony slender, 15 mm. high, with pairs of opposite 

 branches given off almost at right angles to the main stem, with no 

 hydrothecae in the axils ; no hydrothecae below the proximal branches, 

 and none for some distance above each pair of branches; the pairs be- 

 tween the branches and those on the proximal portion of the branch 

 are more distant than the others. Hydrothecae opposite, each almost 

 tubular, regularly curved so that the distal portion is almost at right 

 angles to the proximal portion ; approximately two thirds adherent ; 

 about 1.0 mm. in length. Margin entire but slightly and regularly 

 curved. 



Gonosome. — Gonangia growing out of either one or both of the 

 pairs of hydrothecae at a node; elongated oval, tapering to a narrow 

 neck distally; strongly corrugated. 



Distribution. — Santa Elena Bay, 10 fathoms; San Francisco Bay, 

 2-8 fathoms; Port Utria, 20 and 40 fathoms; Jicaron Island, 15 fath- 

 oms; Pacora Island, 15-25 fathoms; Secas Islands, 25 fathoms; north 

 of White Friars, 25 fathoms; east of islands off Navidad Head, 25-35 

 fathoms. 



Family SertulaHdae 



Genus DIPHASIA 

 Diphasia paarmani Nutting 



Diphasia paarmani Nutting, Am. Hyd., Part II, 1904, p. 111. 

 Distribution. — Reef north of entrance to Tagus Cove, low tide. 



Genus PASYA 

 Pasya quadridentata (Ellis and Solander) 



Sertularia quadridentata E. and S., Nat. Hist. Zoophytes, 1786, p. 57. 



Pasythea quadridentata Nutting^ Am. Hyd., Part II, 1904, p. 75. 



Distribution. — Reef north of entrance to Tagus Cove, low tide; 

 Santa Elena Bay, 5-7 and 10-12 fathoms; La Plata Island, low tide; 

 Pacora Island, 15-25 fathoms; Santa Maria Bay, 10 fathoms; South 

 Bay, Cerros Island, 10-15 fathoms. 



