VIII INTRODUCTION. 
the first four comatulids, the last three stalked, and collected only a single specimen of a 
single species in four others : 
Thysanometrinae Apiocrinidae 
Atelecrinidae Plicatocrinidae 
Of the genera the one especially interesting type absent alike from the "Challenger", 
"Siboga" and "Albatross" collections, but dredged by both the "Investigator" and the "\'aldivia", 
is Coiuaslrocrinus (Teliocrinus), a beautiful pentacrinite related to Hypalocrimis which ranges, 
so far as is now known, only from western Sumatra to the western coast of India. 
The features of special interest in connection with the "Siboga" collection are thirteen 
in number : 
1 . The discovery of an entirely new type of Atelecrinidae with live arms and no 
basals [Atopocrmus). 
2. The discovery of the extraordinarily small bourgueticrinoids of the genus Monacho- 
crinus {ininimus and poculuni), a genus not heretofore known from the East Indian region. 
3. The discovery of an e.\tremely small bourgueticrinoid of the genus Bythocrinus 
{nodipes), a genus not heretofore known from the East Indian region. 
4. The discovery of an exceedingly large bourgueticrinoid of the genus Deniocrimis 
(weberi), a genus previously known only from the Atlantic, though probably the genus referred 
to by Korotneff under the name Rhyzocrinus. 
5. The discovery of a close relative of the European genus ^hitedou {^Eiiantedon) which, 
with the allied genus Mastigometra, represents it in the east. 
6. The discovery of a new type of the genus Atelecrimis with short cirri and very 
large basals {^Atelecrimis anomalus). 
7. The discovery of three remarkable species of Eiidiocrimis two of which represent 
entirely new types, while the third represents a type hitherto only known from southern Japan. 
8. The discover)- of two entirely new types of the genus Xcoincira (represented by 
N. diana and A*, sidogae), one of which has been recently found by the "Endeavour" off 
Western Australia. 
9. The discovery of three tropical species of Coinpsonictra, two of which are of extremely 
small size {iris^ longicirra and parvifiord). 
TO. The discovery of three small species of Decainetra [parva, laevipinna and muiinid) 
which link this genus with Proinetra and with Oligometra. 
11. The discovery of three small species of Psathyrometra {minima, inusitata and 
anomala) which almost bridge the gap between the Zenometrinae and the Bathymetrinae. 
12. The discovery of an extraordinary series of nine species in the families Comasteridae 
(Capillaster gracilicii'ra^ Capillaster teniiicirra^ Comatu/a temiicirra, Coi/iastcr sidogac), Himero- 
metridae {Heterometra propinqiid)^ Mariametridae {Oxyttietr'a tetiuicirra, Dichrometra ienuicirra^ 
Mariametra temdpes) and Colobometridae [Cy/lometra gracilis) all of which are very closely 
related to previously known types from which they differ in possessing long and slender long- 
segmented cirri ; all but Oxymetra tcnuicirra, Mariametra tcniiicirra and Cyllomctra gracilis 
come from the warm, shallow and muddy Java Sea. 
