128 



YORKSHIRE DIATOMS IN 1905. 



M. H. STILKS, F.K.M.S., 

 Doncdstci . 



As a sapplemenl to Mr. R. H. Philip's interestini^ report on 

 Diatomacean i^atherins^s made at two of the Y.N. U. Excursions 

 in 1905, I send the following lists. They are the results obtained 

 from g-atherini^^s collected at Askern (the Bog" Pond), in March, 

 and at Ilkley (a tiny streamlet running down the side of the hill, 

 near the Tarn and towards the town), in September 1905. 



The whole of the Ilkley list is given, but the Askern list is 

 merely suppleinentary to that published in the ' Naturalist ' 

 for November 1900. 



In going- over my record of the Askern g^athering, I found 

 a note, made at the time of my examination, of the presence 

 of a Fnifnlaria slightly inflated at the median portion of the 



<- "" ■■ III i iiii i ii r i i r»^^'''»> n - M ir'iiii iiii """^ '^t. 

 U'l i iii i ii inn i ii iil iii i ii l ^^ ,i> i li m ^lll lM M ll 1 1 1 n 1 1 i ll l l *^ 



Fragllaria capuciaa var. inflata. 



valve. After reading Mr. Philip's remarks on the occurrence 

 of a new (?) variety of F. capucina in the Roche Abbey Lake, 

 I again turned up the Askern slide, and now furnish a sketch 

 of the Diatom in question. 



The Ilkley gathering is remarkable for the great variety 

 of forms present. 



The Askern Diatoms have not been previously recorded. 

 Those marked thus * are also new to the Doncaster list of 

 November 1900. 



Atnplioni in>alis Kiit/.., \;ii-. (ijfiiiis. 

 Cyinhella CKSpidalu Kill z., var. iiavi- 



t ulifoniiis. 

 CymhcUa siibcequcil is Gniii. 



* ,, gastmides Kut/.., var. 



minor. 

 Stauroneis Siiiil/iii (iriin. 



* Xaviciila liiiiosa Kiilz., var. i>ih- 



hcni/d. 



* ,, ventricosa Doiik. 



,, ellipiicn Kiitz. , var. 



sirtalu. 

 ,, I rid is VMr. 



,, viridiilii I\iilz., fornia 



minor. 

 ,, Rrinhanil a (\v\w\. 



* Xaviciihi Brcbissoitii Kiitz. 



* ,, ciucta Kutz. 



,, Anglica Ralfs. 



,, peregrina Kutz., var. 



mcnisruliis, form Upsal- 



ensis. 



* Ciomplioiwniti gracile Ehr. 



* ,, iiiontanum Schum. 

 R/ioifosp/icii ill curz<aia Grun. 



' Corconi'is scii/vllum VA\r. 



Kunolia lunar is (irun. 

 *Synvdr(i I'tii/r/irriir Kniz. 



var. prr- 

 mini</a. 

 ' ,, I '//III Nitzsch, \ii.v. /ong is - 



siniii. 



Naturalist, 



