36 HYDROIDS COLLECTED BY THE "HUXLEY." 



Thornely, Laura K. 1904. Report on the Hydroida. Ceylon Pearl Fisheries, 



i:>t. ii. pp. 107-126. 3 pis. Eoyal Soc, London. 

 ToRREY, H. B. 1902. The Hydroida of the Pacific Coast of North America. 



Univ. California Publications. Zool., vol. i. pp. 1-104. 11 pis. Berkeley 



California. 



EXPLANATION OF PLATE I. 

 Figs, 1-3. Bimeria arborea, nova species, p. 20. 

 Fig. 1. The hydranth. x 100. 

 Fig. 2. Portion of a branch. x9. G., Gonophore. 

 Fig. 3. The male gonophore. Longitudinal section, x 150. 



Ec, Ectoderm. En., Endoderm. G., Gonads. R., Rudimentary 

 radial canals. P., Perisarc. 

 Figs. 4-5. Bimeria biscayana, nova species, p. 20. 



Fig. 4. Transverse section of the stem of a hydranth. x 180. 



A., Auxiliary tubes. Ec, Ectoderm. En., Endoderm. P., Perisarc. 

 pi. Inner layer of perisarc. P-, Intermediate layers of perisarc 

 forming a coarse mesh-work. 

 Fig. 5. Portion of a branch draAvn to show the arrangement of the hydranths 

 and the auxiliary tubes, x 40. 

 S., Stem of a hydranth which has grown into a branch. A., Auxiliary 

 tuljes growing over the branch and bearing liydranths H^ A', 

 Auxiliary tubes whicli are jjrobably for the upper parts of the 

 colony. H., Hydranths which give rise to branches and are con- 

 nected with auxiliary tubes on S. S*, A transverse section of the 

 stem in this position is shown in Fig. 4. 



PLATE II. 



Bimeria arborea. Collotype plate from a photograph by the author, x r4. 



