CRISTATELLA MUCEDO. C9 



of species which are mostly marine. The first order, in which 

 Cristatella is found, has also been named Hippocrepia^ by reason 

 of the tentacular crown being, as the name implies, of a horse-shoe 

 shape ; the second order is sometimes named Infimdibulata, be- 

 cause the tentacular crown is " funnel-shaped." By much the largest 

 share of attention has been given to the marine species of the 

 second order. Books treat largely of them and prepared slides 

 are abundant, but Professor AUman, by the pubhcation of his 

 Monograph, in 1856, has given a stimulus to researches among 

 our fresh-water species ; and by a careful study of this work, 

 accompanied by exploration in suitable localities, anyone will now 

 be able to add considerably to his own knowledge of the depart- 

 ment now under consideration. Our esteemed ex-president, Mr. 

 Morris, F.L.S., possesses some slides of great beauty illustrative of 

 the marine class of Polyzoa, the organisms having been killed 

 with tentacles fully expanded ; and such slides are of great value. 

 It will be interesting to experiment in a similar way upon 

 specimens of the order in which Phunaiella and Cristatella are 

 placed, so that it may be seen whether the expansions of the 

 lophophores, or tentacular crowns, are capable of preservation. 

 It is possible that as the branch-like expansion in a Plumatella is of 

 a somewhat dense, tough material, the open tentacles may be 

 permanently secured ; but during last summer I failed entirely to 

 preserve any expanded specimens of the Cristatella mucedo ; and I 

 fear this is an impossible achievement owing to the gelatinous 

 character of the sac-walls in which these lovely creatures exist. I 

 have copied from Allman's Monograph (see Plate X.) a drawing 

 of a colony of Cristatella as they appear in the height of summer, 

 clasping with moss-like tenacity the stems of aquatic plants. I 

 have always, myself, found them in the deeper water, although the 

 writer of a paper in Vol. II. of the " Popular Science Review " 

 advises that, in searching for adult specimens of Cristatella, you 

 must lie down flat on the bank, carefully remove the floating algae, 

 and with your eyes close to the surface of the water scan the 

 submerged plants as they grow " in situ," and so secure the 

 specimens. The study of natural history does undoubtedly 

 compel an ardent student to practise all sorts of strange devices 

 in capturing his prizes, and the writer of this paper evidently feels 



