12 YORKSHIRE NATURALISTS' UNION. 



BROUGH, JUNE lOTH, 1878. 



At the meeting on June loth the locaUties explored were 

 Brough, Brantingham, North and South Cave, Welton, &c., all in 

 the East Riding; this being the first occasion on which the Union 

 had set foot outside the border of the West Riding. The East 

 Riding, quoted by Mr. H. C. Watson as the vice-county of 

 South East York, has been far less diligently and systematically 

 investigated than either the West or North Ridings, and hence, 

 in spite of the less variety of physical features which it presents, it 

 is perhaps more likely to yield species hitherto unrecorded for its 

 area than are any of the other vice-counties of Yorkshire. 

 Several such were found at this meeting. The neighborhood of 

 Brough yields habitats of several different categories with a 

 correspondingly varied flora, but the number of plants observed 

 during the day might have been largely increased had the 

 Humber Bank and Walling Fen been more fully explored. 



The flora of the oolitic and chalky soils in the neighborhood 

 of Brough and on the Wolds was a characteristic calcareous and 

 xerophilous one approaching in some of its members, e.g., Carduus 

 eriophorus, a South of England type. Several maritime plants 

 occurred on the muddy shores of the Humber and in the 

 adjoining ditches, as Flantago t/iarifinia, Glaux maritima, 

 Zaruiichellia pedicellata, Enteroinorpha dathrata, &c. The ponds 

 and swamps by the railway, where it crosses Walling Fen between 

 Staddlethorpe and Brough, yielded many aquatic and marsh plants. 

 In these ponds Lemna trisulca was found in flower — a very rare 

 occurrence— its propagation being usually effected by buds spring- 

 ing from horizontal slits in the sides of the fronds. Thesummerof 

 1878 seems to have" been rather favorable to the flowering of the duck- 

 weeds, Levina irisulca having been found by the Goole Scientific 

 Society in flower at Sand Holes near Swinefleet on June ist, and 

 L. minor at Rawcliffe Rabbit Hills on June 22nd. The flowering 

 fronds of L. trisulca are easily recognised by the anterior half of 

 the frond being bent downwards into the water, so that the plant 

 as seen floating has the appearance of an irregular Maltese cross. 



Trans, Y.N.U., 1878. Series E 



