152 Rev. T. Hiucks on the Hydroida. 



aboral tentacles were frequently and energetically clasped 

 together and variously intertwined. The proboscis is opaque 

 white at the top and of a pinkish colour below it. 



On a single polyjiite there were traces of the reproduc- 

 tive bodies ; but they were in too radimentary a condition to 

 allow of any conjecture as to the probable course of develop- 

 ment. They were produced at the base of the filiform tenta- 

 cles, forming a circle Avithin the verticil, and presented much 

 the same appearance as those of Tubularia at a similar stage. 



IV. LAFOiiiNA TENUIS, Sars. 



This remarkable Hydroid, which was first noticed by the 

 elder Sars, and afterwards more fully described and figured 

 by his son, is an interesting addition to our fauna. I have 

 obtained it creeping over other zoophytes, which were dredged 

 in Shetland. 



I am also inclined to think that it occm-s on the North- 

 umberland coast. In a letter from the late Mr. Alder accom- 

 panying some specimens of what he believed to be Cuspidella 

 hitmili's, mihi, he writes, " "What are the blunt spine-like 

 processes parasitical on the Cellularia with C. humilis ? 

 Have they any connexion with the latter?" I have little 

 doubt that the supposed Cuspidella was, in fact, Lafoeino. 

 (the two bearing the closest resemblance, so far as the calycles 

 are concerned), and that the " spine-like processes " were the 

 curious sarcothecal organs with which the latter is furnished, 

 and which are thickly distributed along its creeping stolon. 



I draw attention to the matter in the hope that some of our 

 excellent northern naturalists may be on the look-out for the 

 Lafoeina, and may have the opportunity of settling the ques- 

 tion as to its geographical range. 



EXPLANATION OF PLATE XII. 



Fig. 1. reriyonimus ? 7i2dans, n. sp., Ilincks, highly magnified. 



Fiy. 2. I'lumidaria siliqiiosa, n. sp., Hincks, natural size. 



Fig. 3. The same, portion of a shoot bearing two female capsules, 



magnified. 

 Fig. 4. The same, a single calycle and male capsiile, magnified. 

 Fig. 5. The same, a single calycle, more highly magnified. 

 Fig. 6. The same, a female capsule, magnified. 

 Fig. 7. Tentaculoid appendages of Podocoryne carnea, Sars. 

 Fig. 8. One of the same, more highly magnified. 



