16 HALECIUM MACROCEPHALUM. 



Just within the everted margin of the hydrophore is the circle of minute 

 brilHant points which is scarcely ever absent in any species of Halecium. 



Halecium capillare. 

 Thoa capillaris Pouutales, Bull. M. C. Z., I. No. 6. 



PL XL Fi(j8. 5, 6. 



TropJwsome. — Hydrocaulus attains a height of about an incli and a half, 

 slender, irregularly branched, fascicled at the origin of the main stem and 

 principal branches; internodes rather long. Hydrophores short, nearly 

 c^'lindrical. 



Gonosome not known. 



Dredged five miles S. S. W. of Sand Key from a depth of from 90 to 100 fathoms. 



This is a small and delicate species. The circle of brilliant points which 

 in almost every species of Halecium occurs just within the margin of the 

 hydrophore is not here obvious. 



This is one of the specimens examined by Mr. de Pourtales, who has 

 assigned to it the specific name here adopted. 



Halecium macrocephalum. 

 PI XII. Figs. 1-5. 



Trophosome. — Hydrocaulus attaining a height of about two inches, rigid, 

 stout, and very irregularly branched in all directions ; main stem and 

 principal branches fascicled, becoming monosij^honic distally; internodes of 

 moderate length. Hydrophores suppressed. Hydranths very large, sup- 

 ported directly on the fixed lateral processes of the stem. 



Gonosome. — Gonangia springing from the sides of the lateral processes 

 which support the hydranths ; female slipper-shaped, with the orifice situ- 

 ated near the middle of one side ; male smaller than female, cylindrical, 

 with truncated summit. 



Dredged off Saiul Key from a depth of 120 fathoms. 



Haleciwn macrocepfiahim is remarkable for the suppression of the hydro- 

 phore, whose sole representative is found in the narrow membranous lip, 

 which is here quite sessile on the fixed bracket-like process of the stem. 



In some of the specimens the form of the hydranths was well retained. 

 These were very large, reaching when fully extended the height of about 

 two internodes of the stem. 



