14 J. LINDAHL, 1'ENNATULIU-SLÄGTET UMBELLULA CU\ . 



SUMMARY. 



Penuatulidic Köll. 



Tribe: Pennatuleae Köll. 

 Fam. 1. Penniformes KöLL.: Coral peu-sliapcd ; pinnules well developed. 



Fain. 2. Virgulariece KöLL.: Coral pen-sbaped; pinnules small or wanting; polypes provided with calyces; 

 zoöids mostly lateral; rachis several times as long as the peduncle. 



Fara. 3. Frotoptilew KÖLI. : Coral dcstitute of pinnules, distinctly bilateral on its ventral side only; 

 polypes with calyces; zoöids dorsal, lateral and ventral; raeliis twice as long as the peduncle. 



Fara. 4. BathyptilecE Köll.: Coral destitutc of pinnules; polypes lateral without calyces; rudimentary 

 polypes, containing the gcnerative products, lateral on the upper part of the peduncle; zoöids scattered, ventral; 

 rachis about half as long as the peduncle. 



Fam. 5. Umbellulece n. : Coral bilateral, destitute of pinnules; polypes, without calyces, of two different 

 kinds: the lateral polypes arranged in one longitudinal series on each side of the rachis, the smaller, but still 

 perfcctly developed dorsal polypes, arranged in soinewhat irregular, transverse rows (no gcnerative products werc 

 found in any of the examined polypes of either kind); zoöids in separate areas, crowded, lateral and ventral; 

 rachis about one fortieth part (V40) of the peduncle. 



Calcareous axis quadrangular, with a deep longitudinal groove on each side. 



This family, Umbelluleie, eontains two genera, hitherto known: 



Genus: Unibellula Cuv.: The transverse section of the axis four-lobed, with the notch in its ventral 

 side rounded and the notch in each of its other thrce sides nearly rectilinear, forming an angle pf about 90°; 

 uucleus or central raass doubly cresceutic; the whole coral destitute of calcareous spicules. 



Genus Crinillura v. u. Hoev.: The transverse section of the axis four-lobed with a rounded notch 

 in each side; nucieus circular; calcareous spicules ? 



Of the first raeutioned genus fivc specimens are noticed by naturalists. Two of thera werc described by 

 Ellis and Mylius in 1753, but the descriptions do not give a fair idea of their organisation ; another speciraen, 

 aunounced to have been dredged last sumraer by the Challenger-expedition, is not yet described. The two speci- 

 mens, that have aflforded materials to the present description, difter in several respects as well from one another 

 as from the descriptions, published by Ellis and Mvlh s, and in consequence may be regarded as represen- 

 ting two new species, until further explorations of the raarine abysses perhaps will exhibit the interraediate forms. 



Sp. 1. UMBELLULA ENCRINUS L. 



The bodies of the polypes longer than their tentacles, the relation being about 100 : ^B. 



Ha b.: In the North Polar Sea, Lat. 79' N., 80 miles oflf the east coast of »Greenland» or more pro- 

 Ijably the western coast of Spitzl)ergeu, in old tinies very often named Greenland by the whalers, depth 23G lathoras,- 

 iwo specimens were found by Caplain Adrians, Commander of the english whaler »Bntannia» in the suramer 

 1753. Both specimens are long ago lost to science. 



Sp. 2 UMBELLULA MINIACEA n. 



The bodies of the lateral polypes shorter than their tentacles, the relation being, at least in some in- 

 stances, 100 : 295. A zoöid-beariug area covering the outside of the base of the terminal polype; the rachis = 

 '/s the length of the upper swelling of the pedutiele; the whole lop (rachis and the upper swelling) of the coral 

 twisted spirally, and the distal end of rachis curved in between the two upperniost lateral polypes. A minious 

 epitheliuui oceurs very frcciuently, lining the internal cavities as well as several parts of the outside of the coral, 

 especially the mouth of the polypes, the oral surface of their tentacles and the zoöid-bearing areas. The muscular 

 system well developed. 



