2b2 CONTRIBl riONS PKOM I II I NATIONAL HERBARIUM. 



Actinoryclus P elongatus Grun Van Heur. Synop. pi 1881. 



I am in harmony with Van Heurck in doubting the correct m bb of calling this an 

 Actinocyclus. Not only tin- extreme contrast of this elongated form with any known 



►cyclua my Bpecimen is twenty times as long as wide), but the absence of any 

 true peeudonodule makes this classification unsatisfactory. In my Bpecimen at least, 

 the dot which Grunow considers a peeudonodule is only an enlarged bead on the upper 

 Burface of the valve, an« 1 lacks the Bhimmering appearance of the true peeudonodule. 

 In my form also, as in Van Heurck's figures, there are two Buch, located at short dis- 

 tances from the two ends. Rattray states that the peeudonodule is genuine in ■ 

 valve, I >ut doubts its genuineness in another subspecies which Grunow i'"i" 

 that reason names . I < longatus dubia.b The fact is, we have here another illustration 

 of tin- difficulty "i" considering Actinocyclus anything more than a Bubgenus i 

 cinodiscus. Compare the figures of Van Heurck h with that of ( 'oscinodiscus elm 

 ( Iran, in figure 14 of t he same plate. 



Found at Btation 2919, off the coast of southern < California. 



Actinocyclus interpunctatus Bright.) Halt's in Pritch. Hist. Enfus. ed. 



Elatt. Journ. Quek. Micr. Club II. 4: 203. 1890. Not H. L. Smith typ. no. L2. 

 Actinoptychus interpunctatus Bright. Quart. Journ. Micr. Sci. 8:'.H. pl.6.f. /.. 

 Hyalodiscus stelliger Bail. err. det. Moll. Amer. Journ. Micr. 2: LOO. 1877. 

 Eupodiscus Actinoptychus) interpunctatus Bright.; Grun. Amer. Journ. Micr. 8: 



101 L02. L878. 



The above is perhaps a broad variety of A, ralfsii (W. Smith) Elalfs, and differs little 

 from A. sparsus (Greg. Ratt. The slide in II. L. Smith's type no. 12, bearing the 

 above name and identical with his slide 421, marked "Podosira maxima Grun.," is 

 better considered a variety of .1. ralfsii, that is, if that Bpecies and this one are to be 

 kept separate. Elalfs was himself doubtful about this form being a valid spe< I 



.-hare this doubt. Still, as their is ground for question on this point, it is perhaps 

 best to accept Etattray's decision and retain the above name. 



Found at Btation 1505H. 



Actinocyclus minutus Grev.; Rati. Journ. Quek. Micr. Club II. 4: 170. />l. 11. f. .',. 

 1890. 



Tim original specimens came from Manila: this one from the Galapagos Islands. 

 Found at Btation 2807, Galapagos Islands. 



Actinocyclus oliverianus O'Mcara. .lour. I. inn. Sue. Bot. 15: 58 pl.l.f.7. L876 (?). 

 ;r. Rep. Voy. Chall. Bot. 2: L45. pi ;./.;. L886. Etatt. Journ. Quek. Micr. 

 Club II. 4: L48. L890. 

 Podosira oliveriana Grun.; Van Heur. Synop. pi. 118. f. 5. l^ s i 

 M opodiscus oliverianus Grun.; Van Hem-. Synop. pi. 118. f. 5. L881; Denkschr. 



Akad. Wien 48-: 79. L884. 

 Actinocyclus wmbonatus Castr. Rep. Voy. Chall. Bot. 2: L45. pi. \.f. i. 18£ 



I I is difficult to decide on the genus of this diatom. It has the Bhimmering pseudo- 

 aodule of Actinocyclus, the watch-case milling of Podosira and the general herder of 

 Craspedodiscus. I place it as above because my form, unlike that figured by Van 

 Heurck and the one referred to by Rattray, has a true pseudonodule, a Large, hyaline. 

 refractive globule, and uot the small process of Van Heurck's and Rattray's figures. 

 The view of Van Heurck and of Grunow, who looked on this as a Bpecies of Podosira, 

 does not seem to me to be tenable. Ii may be found uecessary to adopt Grunow's BUgf 



o Journ. Quek. Micr. Club II. 4: 197. 1890. 

 '-V;iii Heur. Synop. pi. 125./. 16 17. 1881. 



