202 THE ROYAL SOCIETY OF CANADA 



a. Gonangia not specially protected, hydrocladia pinnately 

 arranged; each hydrocladium bears more than one hydro- 

 theca Plumularia 



Genus AGLAOPHENIA 



Trophosome. — Hydro thecal margin provided with sharp teeth, 

 posterior intrathecal ridge present, one mesial and two supracalycine 

 nematophores for each hydrotheca always present. 



Gonosome. — Gonangia enclosed in true corbulae, formed of modi- 

 fied pinnae. There are no hydrothecae at the base of the gonangial 

 leaves. 



Key to the species of Aglaophenia found in the Vancouver I. 

 region. Margin of the hydrothecae with 11 uneven teeth. 



A. Mesial nematophore with an expanded free portion. .A. latirostris 



B. Mesial nematophore with free portion narrowed towards the 



extremity A . striUhionides 



Aglaophenia latirostris Nutting 



PI. XXXIV, Fig. 130 



Aglaophenia latirostris Nutting, American Hydroids, pt. 1, 1900, 



p. 101. 

 Aglaophenia latirostris Fraser, West Coast Hydroids, 1911, p. 80. 



Trophosome. — "Colony unbranched, attaining a height of about 

 2 inches stem not fascicled, divided into regular internodes, each of 

 which bears a hydrocladium; hydrocladia lying in the same plane, 

 alternate, closely approximated and projecting at right angles from 

 the stem; hydrocladial internodes distinct, each with a septal ridge 

 behind the intrathecal ridge. Hydrothecae closely approximated, 

 obconical, margin expanded and surrounded by eleven very irregular 

 jagged teeth, the anterior being retrorse, the next directed forward, 

 the remaining four on each side being in two pairs of sharply pointed 

 teeth; intrathecal ridge evident, oblique, reaching nearly around the 

 hydrotheca; lateral nematophores rather small for this group, not 

 reaching the top of the hydrotheca; mesial nematophore very large, 

 adnate to the front of the hydrotheca nearly to the top and then 

 projecting forward into an expanded spout-like distal extremity, 

 which often reaches a considerable distance in front of and above the 

 hydrotheca" (Nutting). 



Gonosome. — "Corbula closed, composed of about eight pairs of 

 moderately narrow leaves, each of which bears a row of nematophores 

 on its distal edge and another on its inner proximal edge as in A. 



