HYDROIDA II 



25 



the name of Lictorella Levinseni, and notes the nematothecse as among its characteristic features; his 

 colonies, which I have had an opportunity of examining, are fertile, wherefore he was also able to 

 describe the gonosome. This is of a highly peculiar character, and at once demonstrates the incorrect- 

 ness of Stechow's supposition (1912 p. 114) that the species should be identical with Zygophylax 

 armata (Ritchie). Ritchie's species (1907 p. 533) has a typical coppinia, the tubes of which are each 

 furnished with several nematothecse. 



The single gonothecee in Zygophylax biarmata resemble not a little those of Lictorella pinnata, 

 the number of opening tubes, however, being apparently in Zygophylax biarmata constantly reduced 

 to two, the tubes being at the same time somewhat longer. The single gonotheca stands out freely, 

 but the gouothecse are closely packed in clusters on the stem or main branches, and between them 

 we find numerous long nematothecae, remarkably well developed, so that the whole aggregate must 

 be regarded as a primitive coppinia, or rather as something between the open scapus and the coppinia. 



There are one or two points which seem to count against the identity of Lictorella Levinseni 

 and Zygophylax biarmata. Sasmundsson's description rather gives the impression that there are 

 not, normally, a pair of nematothecse on the apophysis; on closer investigation, however, we are led 

 to the conviction that there are, as a rule, a couple of holes in the periderm showing that nemato- 

 thecse have been there, but have fallen off. The colony investigated is the same which Ssemunds- 

 sou shows in fig. 2 a. — A further difference would seem to exist in the hydrotheca stalks, which in 

 Ssemuudsson's specimens are somewhat longer in proportion than stated by Billard. The length 

 of stalk, however, varies considerably in hydroid species, and cannot thus be used as a specific char- 

 acter. And finally, the hydrothecae in the colony here concerned exhibit a tendency to unilateral 

 arrangement Ssemundsson does not mention this feature, nor does Billard make any reference 

 to the same in his exposition. It would nevertheless seem, from Bil lard's figure (1. c. text fig. 8) 

 that the hydrothecse point obliquely forward towards the one side, the hydrothecse shown being indic- 

 ated in oblique projection, with the aperture directed slightly forward towards the observer. Here 

 again then, there is nothing which can be taken as evidence of distinction in species. 



The find here recorded extends the known distribution of this deep-sea form considerably 

 towards the north, the species having hitherto been known only from the Bay of Biscay and south 

 of the same. It appears to belong to the abyssal region. 



Family Campanulinidae. 



The hvdrothecse are tubular to bell-shaped, sessile or stalked, of the radially-symmetrical type, 

 more rarely with diaphragm. The hydrothecse are furnished with highly organised closing apparatus, 

 falling in the shape of a roof or a pyramid over the indrawn polyp. The colonies are stolonial or 

 sympodial. The polyps have a conically pointed oral part, and gastral endoderm of uniform organisation. 



The generic division of this family has given rise to much dispute, and we even find, that 

 certain writers, such as Schneider (1897) and Bonne vie (1899) regard it as a single genus. The 



The Ingolf-Expedition. V. 7. 4 



