150 Rev. T. Hincks on Beep-water 



This elegant form is not uncommon amongst tlie Icelandic 

 dredgings, creeping over other Hydroids. 



Cuspidella Jiumilis^ Hincks. 

 Creeping over the stems of Halecium crenulatum. 



Lafoeina tenuis j M. Sars. 



This remarkable Hydroid, first described by the elder Sars, 

 and figured by his son in his recent paper on Norwegian 

 Hydroida, occurs amongst the Icelandic dredgings, creeping 

 over other zoophytes. The species may readily be mistaken 

 for the Cuspidella humilis (mihi), from which it is chiefly di- 

 stinguished by the very remarkable sarcothecaj with which it is 

 furnished. In preserved specimens these may be easily over- 

 looked. 



Filellum serpens^ Hassall. 



Creeping over the stem of other zoophytes. It has a wide 

 distribution on the Norwegian coasts, and occurs at great 

 depths as well as in shallower water. 



Lofoten, from 300 fathoms [G. 0. Sars). 



Family Haleciidae. 

 Halecium muricatum^ Ellis and Solander. 



A few fragments with reproductive capsules. 



This species has been found off the coast of Labrador. 



Halecium crenulatum^ n. sp. PI. YIII. figs. 21-23. 



Stem compound, branched ; branches straight, regularly 

 crenulated above each joint. Hydrothecce supported on very 

 short lateral processes, single or in pairs, alternate, elongate, 

 expanding gradually towards the margin, which is slightly 

 everted, twisted at the base, bearing a strongly annulated 

 branchlet given off from the side. Gonothecce ovate, shortly 

 stalked, springing singly or in pairs from the lateral process 

 beneath the calycle. 



• The above diagnosis is of necessity defective ; for though 

 many fragments of the species occur amongst the Icelandic 

 dredgings, I have not met with a specimen in a perfect con- 

 dition, nor even with a piece of any considerable size. From 

 an examination of the fragments, I am able to say that in its 

 mature state it possesses a compound stem ; but of the habit I 

 can give no account ; the portions from which my description 

 is chiefly taken are either detached branches or imperfectly 

 developechshx)Ots. The minute characters, however, are suffi- 



