12 Mr. J. J. Queleli on some 



or not at all perceptible ; but on placing the specimen in 

 water it assumes its normal habit. 



The gonosome consists of gonothecse, which are borne 

 neither directly by the hjdrocladia nor by modified protective 

 branches, but are seated directly on jointed appendages of 

 the hydrocladia, one gonotheca to each joint. These appen- 

 dages are placed laterally at the upper basal part of the mesial 

 nematophore, immediately below the base of the hydro theca, 

 and are always situated on the left side — left, that is, to one 

 standing in the hydrotheca, so to speak, and looking towards 

 its pointed margin. They are unbranched and jointed, and 

 are placed either on consecutive mesial nematophores or 

 irregularly. The joints are similar throughout, generally 

 three or four in number to each appendage, narrowed at the 

 base and expanded at the top, so as to be obconical or sub- 

 triangular ; the expanded upper lateral edges chiefly formed 

 by two rather short nematophores, one at each edge, between 

 which is placed the narrow base of the joint above, while 

 below this point of juncture and on the front of the joint (that 

 is on that part which looks towards the hydrotheca below 

 which the appendage is situated) is seated the gonotheca, 

 which thus occupies the upper anterior portion of the joint. 

 The remaining anterior portion of the joint is evenly divided 

 by two transverse constrictions. 



The gonothecse are sessile and elongato-pyriform, with a 

 suboval subterminal orifice ; they are placed one on each 

 joint of the appendage, and, where broken away, leave their 

 base of attachment exposed to view. 



From the structure of the parts thus described it will be 

 seen that the genus Streptocaulus calls to mind the peculiar 

 condition found in Cladocarpus^ in which the ramuli bearing 

 gonothecse are not strictly modified hydrocladia, but appen- 

 dages of the hydrocladia, with this essential distinction, 

 however, as it seems to me, that while in Cladocarpus these 

 structures may possibly be imagined as being more or less 

 protective, and thus as peculiar forms of the phylactocarp 

 according to the definition of Prof. AUman, yet in Strepto- 

 caulus they can in no sense be considered as protective, but 

 seem rather to be a repetition on a more complete scale of the 

 structures found in such a genus as Schizotricha. 



In 8cliizoiricha the gonothecse are not strictly borne by the 

 hydrocladia, but on a basal portion which seems strictly 

 homologous with the reproductive ramuli of Cladocarpus. A 

 multiplication of such parts as the basal segments of Schizo- 

 tricha, giving a jointed ramulus, in which each joint bears 



