74 
NATURE 
[May 28, 1885 
forms we have mentioned, which are dealt with in detail, 
frequent references are made to other examples in which 
equally good or further illustration of special features may 
be obtained. Similar thoroughness runs through the 
accounts of all the types. 
Every one perusing the volume must be impressed 
with the high standard of its educational value. 
Teacher and student in this country are alike to be con- 
gratulated upon its publication. The former has now a 
thoroughly trustworthy laboratory guide to place in the 
hands of pupils, and the latter has a handbook in his 
own language to which he can refer with confidence in 
his search after a sound knowledge of plant-morphology. 
This is only the first part of the work, and deals with 
Phanerogams and Pteridophytes. May the succeeding 
portion not belong in appearing! It is regrettable that the 
original intention of the authors “ to preface the directions 
for the study of each type with a short account .. . of 
its salient morphological facts” has not been carried out 
in this part; Mr. Thiselton Dyer assigns in the preface 
the reason for its postponement. We are convinced that 
the want of such brief epitomes will be universally felt. 
But as the book is certain of a full measure of success, we 
loo’: forward, with the authors, to the realisation of their 
hope that “the original scheme upon which the work was 
planned ” may be “ carried out in a future edition.” 
We conclude as we began by heartily welcoming the 
volume. We envy a student commencing to work with 
such a guide, and we are greatly mistaken if its effect is 
not very rapidly felt in the botanical teaching of the 
country. 
THE PENNATULIDA OF THE NORWEGIAN 
NORTH ATLANTIC EXPEDITION 
Den Norske Nordhavs Expedition, 1876-1878. Zoologie 
Pennatulida. Ved D. C. Danielssen og Johan Koren. 
(Christiania; Grondahl and Sons, 1884.) 
ast is the twelfth part of the series of monographs 
contained in this fine work, the first part of which 
was published in 1880. The former parts have dealt with, 
besides the chemistry and physics of the expedition, the 
fishes, a part of the Mollusca, the Gephyrea, Annelida, 
Asteroidea, and Holothuroidea, the monographs on the 
last four animal groups being by the same indefatigable 
naturalists who have produced the present memoir on 
the Pennatulida. The work is a highly creditable one to 
all concerned. 
The present part is illustrated by twelve excellent 
plates, two of which are coloured, and which are in the 
same style as those already published by the same 
authors in their well-known memoir on new Alcyonians 
belonging to the Norwegian fauna published two years 
ago." Thirteen species of Pennatulida belonging to eight 
genera were obtained during the expedition, and of these 
eleven species and two genera were new. One of the 
new genera is Svava, a small sea-pen with rudimentary 
fins and devoid of spicules on the sarcosome, cells and 
polyps. There is a stripe of zooids on either side of the 
stem, and in the two lateral canals of the stem are deve- 
loped the zonads on the mesenteries of these zooids. 
The zooids alone produce gonads, the fully-developed 
* “*Bergens Museum. 
; Nye Alcyonider, Gorgonider og Pannatulider 
tilhorende Norges Fauna.” 
(Bergen, 1883.) 
polyps being barren. They are viviparous, the larvae 
escaping from their mouths, as in Corallium. The other 
new genus, Gunneria, is founded on a fragment of a single 
specimen, but it is characterised by the presence of an 
immense quantity of spicules on the bodies of the polyps, 
their tentacles, and the sarcosoma, which latter forms a — 
regular calcareous crust on the walls of the cells; the 
spicules are so closely packed in several layers that it is 
difficult to separate them, even with caustic potash. 
this respect Gunneria approaches the Gorgonidze ; yet it 
is, nevertheless, a true Pennatulid. 
The main feature of the memoir is, however, the part 
which relates to the now famous deep-sea Pennatulid, 
Umébellula encrinus, to which more than half the letter- 
press and seven of the five plates are devoted. 
The Norwegian Expedition obtained twelve specimens 
of Umbellula encrinus from different localities. Kolliker 
described eight species of the genus from the Challenger 
collection, but one of these, U. magvifiora, is considered 
by the authors as referable to the old historical UW. 
encrinus, as are also Lindahl’s new species from the 
Swedish Expedition of 1871, viz. U. miniacea and U. 
pallida. The whole of the twelve specimens obtained by 
the Norwegian Expedition are here carefully described in 
all details. All of them differ from one another, display- 
ing peculiarities in various ages and stages of develop- 
ment which might, were the series less complete, easily 
lead to the establishment of separate species. The largest 
specimen obtained was dredged from a depth of 763 
metres. Itis a giant indeed. The rachis and the polyps, 
of which there are forty in the bunch, are twice figured 
on the last two plates, of actual size, coloured and un- 
coloured. The bunch of polyps occupies with its breadth 
nearly the entire length of the folio plate. The plates are 
far the finest representation of Umbellula yet published. 
There are eight prominent lanceolate areas occupied by 
In| 
—— 
a 
zooids which extend up between the lateral polyps on the © 
calicle-like part of the rachis, and spread themselves 
inferiorly over the rachis generally. The zooids are 
described as having each a single protusible tentacle, the 
tentacle when not retracted looking like a pendent papilla. 
These tentacles sometimes, but not always, bear short 
lateral pinnules, which are hollow, their cavities commu- 
nicating with those of the tentacles, and which can be 
retracted with them. Kdolliker, in his account of the 
Challenger Pennatulids, described similar zooids each 
bearing a single tentacle as existing in Umbellula Huxley 
and U. Carfenterz, and in the latter species found the 
single tentacles branched. He figures them, but only on 
a very small scale. On looking at the figures here given 
of these zooids (Tab. X., Figs. 56, 57) it is very difficult 
to understand their structure: the position of the mouth 
is not shown in any one, and they are drawn as elongate 
and flask-like in form when expanded, squat and rounded 
when retracted. The tentacle seems when protruded to 
be a direct narrow prolongation of the entire body of the 
zooid, and it appears as if on retraction this prolongation 
were telescoped into the basal region of the body. The 
base of the single tentacle should abut on one side of the 
mouth, but no such mouth-opening is figured. In the 
enlarged view of a zooid (Fig. 57) the mouth is neither 
definitely indicated nor referred to in the description. 
The text is not at all clear on the point. 
