940 Transactions of the Society. 



these somewhat interrupted at a number of annular rib-hke pro- 

 jections varying in number; these projections most numerous 

 towards the upper third of each segment." — Barker, in Proc. Dub. 

 Micr. Club, QJ.M.S., 1869, p. 194. As I do not know of the 

 publication of any measurements or authentic figure of this inter- 

 esting and unique species, I may possibly be in error in referring 

 these American forms to it ; the figures therefore must speak for 

 themselves, though, owing to the dense dark endochrome, drawing 

 was difficult. Frond, fig. 26a; fragment, showing apex more 

 clearly, fig. 26&. 



Long. 227-260 /i = •0089--0102 in.; lat. max. 23-31 fx, 

 = "0009- "00122 in. Specimens from near Minneapolis, Min- 

 nesota, U.S.A. Not previously reported from America. 



GoNATOZYGON De Bary. 



27. G. sex-spiniferum nov. sp. Joints variable in length, ten 

 to thirty times the breadth; base swollen, apex either rotundo- 

 truncate or quite rounded ; spines (or rather setae) very short, and 

 arranged longitudinally in six linear series. Forming long fila- 

 ments. Minnesota, U.S.A. 



Long. 88-191 fi = -00346- "0075 in.; lat. 6-8-5 /* = 

 •000236-33 in. Fig. 27. 



The figures which illustrate these remarks are all drawn by 

 myself from nature, and to a uniform scale of x 500. 



