STEM EELWORMS. 



21 



specimens soon began to recover power of active movement in the 

 warm room, and likewise some of the older specimens, whilst I con- 

 tinued examination. The Clover was the " Common Eed Clover," 

 Trifolium pratense, but the seed was mixed of two different kinds, about 

 two-thirds "English Bed," and one-third "Russian Red," and sown 

 in the preceding April " in the usual way in a corn crop." 



On February 14th, specimens were sent me by Mr. Arthur Alse- 

 brook, from the Yorkshire College, Leeds, of diseased Clover plants 

 and maggots, which proved to be (as above) of Sitones, or Clover-leaf 

 Weevil, with the observation that he considered the larvae appeared to 

 be the cause, in the East Riding of Yorkshire at least, of the dying off 

 of the Clover, "which is so prevalent throughout many parts of the 

 country." On examination, I found that, besides the weevil maggots, 

 there was Stem Eelworm attack, but only a few of the Eelworms 

 noticeable, for the samples of diseased growth sent were very small. 



On the 18th (that is, four days later) Mr. Alsebrook wrote to me 

 again, requesting my opinion on a series of specimens of Clover, of 

 which he wrote : — 



" They are all from the same district (near Howden, in the East 

 Riding), and were taken by me yesterday and to-day. 



" No. 1 had many weevil larvse in it, which I have kept. 



"No. 2 has many thread-like worms, of which I should be glad of 

 particulars. 



" No. 3 has at the roots of one plant some very peculiar growths, 

 which I should also be glad to have particulars of." — (A. A.) 



These specimens I examined, and in the case of "No. 1," from 

 which "many weevil larvae " had been taken, I did not find that there 

 was injury attributable to Sitones maggots, but there were live Eel- 

 worms present in the stem part of the abortive bud examined. 



" No. 2," small worm-like creatures, from size, shape, and presence 

 of a brown head with two antennae, presumably a species of Sciara 

 (a two-winged fly), and feeding on decayed matter.-'' Eelworms of 

 different sizes present and in active condition. The red maggots of a 

 Cecidomyia, or Gnat Midge, were also present. These little larvae are 

 legless, cylindrical, pointed towards the head end, and are especially 

 recognizable by having beneath the body (near the head) a horny 

 organ, known as the " scraper" or " anchor process." This coubists 

 of a narrow stem, of which one end is fixed to the larva. The other 

 end, which is free, and enlarged, and points forward, varies much in 

 shape ; sometimes it is bifid, but in the present case is widened and 

 prolonged in the middle into a somewhat flattened triangular shape. 

 The maggots consequently were presumably larvffi of the Clover-leaf 

 Midge, Cecidomyia trifolii, now in hybernating state, which, when in 

 * See 'Farm Insects,' by John Curtis, pp. 460, 461. 



