Dr. J. V. Barboza du Bocage on Hyalonema boreale. 37 



curious example of Hyalonema lusitanicum^ in which there are 

 two bundles of filaments to a single sponge, nearly as in the 

 annexed drawing (p. 36) . Now I can perfectly conceive that the 

 two bases, originally distinct, have become confounded together 

 with increasing age ; but I cannot understand this confusion 

 if we are to assume that the natural position of Hyalonema 

 is the reverse of that indicated in my sketch. 



I am now convinced that Hyalonema is a sponge. As to 

 the polypes (Palythoa fatua^ Schultze), I regard them as para- 

 sites. I have several specimens oi Hyalonema with other para- 

 sites : two are covered with an Antipatharian, three abso- 

 lutely destitute of polypes and sponges, one embraced by the 

 foot of an Actinia of what seems to me a new species. It is a 

 flesh-coloured Actinia of enormous size. 



I am still suffering from my recent illness. As soon as I 

 am a little recovered, I shall endeavour to publish some sup- 

 plementary notes upon the discovery of our learned friend 

 Lovdn. 



Believe me, always your devoted friend, 



J. V. Barboza du Bocage. 



My dear Friend, Lisbon, May 10, 1868. 



After a more careful examination of our two little sponges, 

 I have arrived at somewhat different results, which I hasten to 



Fig. 1. a, head ; h, stem ; c, base. Fig. 2. Aggregation of linear spi- 

 cules forming the stem. Fig. 3. Interior of the head to show the radiating 

 bundles. Fig. 4. Spicules implanted perpendicularly upon the head and 

 base. Fig. 5. Spicules of the radiating bundles. Fig. 6. Spinous spicules 

 of the sarcode of the stem. Fig. 7. Spicules of the stem or axis. 



