HA RD WICKE' S SCIENCE- G OS SIP. 



243 



I have now to describe the worm from Bangor, 

 which very nearly resembles Eisen's species in some 

 respects, though it is abundantly distinct therefrom 

 in others. 



Allurus tetragonurus (Friend) is about one and a 

 half inches in length, somewhat cylindrical before, 

 quadrangular behind, and tapering from the girdle 

 towards each extremity, so that the latter portion of 

 the tail is only one half the diameter of the girdle. 

 This latter organ is very prominent, of a yellowish 

 orange colour, and closely fused, so that the segments 

 are only distinguished with difficulty. The fore part 

 of the body is sienna brown, the hinder part a dull 

 yellow brown, closely resembling the light variety of 

 Allurus, (A. luteiis, Eisen, not A. Jlavus, Friend). 

 The total number of segments is about eighty-five. 

 The head is very small, and does not cut the first 

 segment. The male pores are also very small and 

 inconspicuous, but are certainly situated on segment 

 thirteen as in the other species of Allurus, and not 

 on the twelfth, as in Eisen's Tetragonurus. The 

 position of the male pores is a point of great im- 

 portance in the identification of genera, but the 

 method of attachment between the lip or head, and 

 the first segment or peristomium is so variable, that 

 it cannot be relied on as a key to genera, though it 

 may be of particular value for specific purposes. I 

 have shown this in connection with a small Dendro- 

 Ixena or tree-worm which was formerly called Lum- 

 bricus Eiseni (Levinsen), but is now shown to be 

 closely related to the other tree-worms. 



The question now remains, did Eisen make a 

 mistake respecting the exact position of the male 

 pore ? I dare not insinuate such an idea, because, 

 with the exception of Rosa, we have no foreign 

 authority who can compare with him in accuracy of 

 observation. For the present, therefore, we must 

 assume that we have two worms which are practically 

 identical in every important respect (length or 

 number of segments being no criterion) except in the 

 position of the male pore, which in our British 

 species is on the thirteenth segment, and so ranks it 

 with Allurus, but in Canada is on the twelfth, and 

 thns constitutes a new genus named Tetragonurus. 



Xo. 



Segments occupied by 



Length. 



Seg- 

 ments. 



Colour. 



Girdle. iTubercula. 



Male pore. 



1 18-22 



2 l8-22 



19-21 

 19-21 



12 

 13 



mm. 



25 



3° 



40 

 85 



Brown 

 Brown 



If this is a fact, it must have a meaning, and it will 

 be interesting to observe how future research will 

 enable us to decide the question. Meanwhile it is 

 very pleasant to be able to add another new species 

 to our indigenous list, if not to the records of science. 



The tabular view of the two worms which is 

 appended, will show at a glance the differences and 

 similarities existing between them. No. I represents 

 Tetragonurus pupa (Eisen). No. 2 stands lot Allurus 

 tetragonurus (Friend). 



THE CLOUDED YELLOW. 



THIS year Edusa is apparently everywhere. Down 

 near Penzance my brother has marked his 

 joyous, untiring flight over Cornish meadows ; in 

 Pembrokeshire he has flourished, and become the 

 living flower of the breezy heaths and sweet-smelling 

 clover-fields. Here at Llandyssul he is in almost 

 every open spot. 



I say he because Mrs. Edusa is either very .rare or 

 possesses such a stay-at-home disposition, that, at 

 least by myself, she is the vision of a thing hoped for, 

 and not yet overtaken. In fact, I have made her ac- 

 quaintance only once, and that for a brief moment. 

 I missed with the first stroke, for the reason that as I 

 was preparing to come down she was also preparing — 

 to go up, and she, alas ! had the start. Away she 

 went, gambolling with an admirer in the further 

 realms of blue. Then down came the latter on to a 

 flower. By-and-byshe also descended, but, scurrying 

 across the heath, was soon lost to sight. The approxi- 

 mate colours of the neighbouring rag-wort, together 

 with an awkward tumble into some brambles on my 

 part, had much to do with her disappearance from 

 my excited eyes. 



Concerning the Clouded Yellow, a contributor to 

 Science-Gossip, writing from Ipswich, says : " I have 

 heard two theories given to account for the irregular 

 appearance of these species at long intervals. The first 

 is, that they are blown over from the continent, when 

 they hatch out in August ; the second is, that a few 

 insects coming over in the spring, lay their eggs here, 

 and after passing through the various stages, the 

 butterfly emerges from the chrysalis in the late 

 summer. Either of these ideas seems feasible, but 

 bearing in mind the capture of several Edusse in the 

 earlier months of the year, the latter seems the more 

 probable." I beg to differ from the above opinions, 

 for it appears to me that neither of the ideas is 

 feasible. 



Cardiganshire is too far remote from the Continent 

 for;insects to cover, in one day, the distance between. 

 I may state that after about four days of continuous 

 rain and north winds, when butterflies are scarcely 

 ever abroad, I found, on the following morning, 

 which was bright and sunny, that Edusse were roam- 

 ing perfect and as fresh as daisies, over the clover- 

 fields and up the sunny slopes of the hill-side. If 

 these had come from France, they must have arrived 

 during the sunny weather which preceded the four 

 wet days. And this being the case, they would have 

 been spoiled by the journey and the succeeding bad 

 weather. But to contradict this first theory they all 



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