15 



Keut," but Loudcu's Eiuyiluiia'dia states lliat it was introduced into England from Germany 

 in 1815. It is also mcutioucd in DuunV .Vlicn Flora. 



Of raretics iircviously roiJorted I liavr again found Ambrosia trifida, Anchusa ochroleciia, 

 and Brucastruni jjolliihii. The latter wa.s in blossom as late as December. 



J. JACOB. 



Shcphcrdswell. 



QEOLOQICAL NOTES. 



An immense fall of elift took phue on (Sunday night, December 3lBt, 1911, between 

 Dover and Folkeslouc. This "slide," which is the most extensive that has occurred in 

 this vicinity for some years past, took jilace about nine o'clock at night, the site being 

 Abbotscliff, to the westward of the Wairen. The vast quantity of chalk which slid away 

 from the face of this cliff can best bo judged by the extent of' the debris, which formed 

 a miniature breakwater extending from the foot of the cliff to about four hundred yards out 

 to sea, whilst its width is some two hundred yards, and it is in places thirty feet deep. 

 Such a mass of chalk represents some hundreds of thousands of tons. The cliff at this 

 point is about ;348 feet in height. 



tieologicallv, the ujiper portion consists of the hard concretionary chalk, and a zone of 

 '• Terebretulina' gracilis." Next iu descending order the '■ Belciiinites plenas " bed of only 

 about 4 feet, which is regarded as the upper bed of the lower chalk. Then a white chalk 

 containing " Holaster subglobosus " for 138 feet. -Vfter this, a remarkable bed known as 

 the " ca.st bed," only 2 feet in thickness. It terminates in the grey chalk, and chalk marie, 

 the whole superincumbent beds resting on the Gault Clay. The chalk, especially the upper 

 beds, is very ab.sorbent of moistuie. So that it may be readily understood that the late 

 saturating rains may have added a ten per cent, burden to these cliffs, and if it be taken 

 at only live per cent., this would amount to millions of tons. 



Another factor must be taken into account, and an important one, that these cliffs, 

 resting on the impervious grey chalk, aud Gault clay, have in these a plain of. saturation. 

 This clayey foundation, becoming pl.istie, is squeezed out, letting down huge masses, which 

 are shed off like iceljcrgs into the sea. 



J. GORDON McDAKIN. 



NOTES ON KENTISH LEPIDOPTERA. 



During a short visit to Ashford in July we found in that neighbourhood abundance of 

 the larvae of CucuUia asteris in Golden rod, but only one C. graiihnlii, which was as they 

 usually are, ichueumoned with a single large larva?, which emerged next day, leaving only 

 the skin of C. gnapliulii, f';/»iufi);i(ioru, and Tnenincamim popiiiifi, aud lirephos nuthii and 

 Sphinj- iHipuli were obtained from aspen trees, but only by diligent beatiug. Near Seven- 

 oaks I found for the first time, aljout the end of the month, Gnrhiii" ochmci'a full fed in 

 the stems of burdock in a damp wood. In the open I have never met with it, nor in thistle 

 stems, which it is said to frequent, but iu the latter I have found numbers of a small 

 larva: resembling it iu markings, but evidently belonging to a different group of insects. 



During October, when visiting ivy blossom at night, f was surprised to find Vroptcryx 

 satiibucaiin hanging down by a thii»ad from the flowirs. They appeared to cat the flowers 

 bv ijreferencc, but when sujiiilicd with leaves fed also on them, eating away the sides of the. 

 leaf. I find the Heii'mliis humuli one of the most destructive insects in the garden, and 

 most difficult to eradiiate. The moth Hies low, so near the herliage that it is almost impos- 

 sible to catch it iu a mixed border with a butterfly net, and as it drops its eggs on the soil 

 like small shot they cannot be seen and removed like eggs laid on a leaf, and the disappear- 

 ance of some rarity or the sudden withering of one side of a jjlant such as a pemga chmatis 

 indicates the cueiiiy at work, and digging at this time of year (December) reveals the limp, 

 white, half-starvedlooking larva of nearly 1\ inches long, and of the thickness of a quill, and 

 then it is easily .seen, but later mi forms a thin cocoon, in which e.irth adheres and thus hides 

 it, as it does not, like that of the shark moths, form a firm oval case, but gives to the touch, 

 and it is only when the empty somewhat cylindrical chrys;ilis case is seen on the surface of 

 the ground iii May or June that evidence of its cxi.stenep is found. The only enemy it seems 

 to h,ave in my garden is our Russian cat. which enjoys insect Imnting as much as we do. and 

 sees them better, and kills many of the low flying Ie]iido]itera. 



E. M. HOLMES, F.L.S., F.E.S. 



