THE COLLECTION OE MISS H. QATTT. 155 



two alternate costse ; costse arching over the rhachis from oppo- 

 site sides, and each carrying several pairs of strong opposite 

 spines. 



Locality. Bass's Straits. 



This is a tall, strong-growing species, attaining a height of 

 about 9 inches. The pinnae spring very decidedly from, the 

 anterior aspect of the branch, each internode of the branch 

 carrying a siugle pinna directed alternately to the right and left. 

 A large nematophore is borne by each internode just above the 

 origin of the pinna. 



The phylactocarps are very beautiful objects. They are formed' 

 on the type of the j)hylactocarps of Lyiocarpus {Aglaophenia) 

 myriophyllum. The rhachis is composed of about thirty-two 

 iuternodes^ each internode supporting a single costa, the costse 

 springing altezmately from the right and left sides of the inter- 

 nodes, where each forms a continuation of a short process from 

 the rhachis. To this process it is united by a transverse joint, 

 and besides the pairs of opposite spines it carries near its 

 proximal end a single azygous spine and a pair of short, blunt, 

 closely approximated nematophores. Every internode of the 

 rhachis carries a gonangium, whose point of origin was clearly 

 seen, though the gonangia themselves had all fallen from the 

 specimen. 



GrATTYA, gen. nov. 



Generic character. Trophosome. — Hydrocauhis consisting of hy- 

 drocladia which spring from a creeping stolon or from one another through 

 the intervention of a jointed peduncle, and are divided into distinct inter- 

 nodes, each internode carrying a hydrotheca. Hydrothecse with dentate 

 margin; mesial nematophore fixed, not adnate to the hydrotheca; lateral 

 nematophores moveable. Gonosome. — Gonangia destitute of sfyecial pro- 

 tective apparatus. 



The genus Gattya holds a position intermediate between the 

 typical Eleutheropleau and the typical Statoplean forms of the 

 Plumularidae. To the former it is connected by its moveable 

 lateral nematophores and by the complete separation of the mesial 

 nematophore from the walls of the hydrotheca. To the latter it is 

 connected by its fixed mesial nematophore, and by the dentate 

 margin of the hydrothecse. Notwithstanding, however, its obvious 

 relations to the Statoplean Plumularidse, the presence of moveable 

 nematophores must be held as deciding in favour of its place 

 among the Eleutheroplea. 



