198 



KNOWLEDGE. 



{Septembee, 1901. 



is of a briglifc green coloiir, resembling closely that of 

 the Cladopbora, among ^yllicb it lives. Tbe ■well- 

 developed head with strong mandibles working at an 

 angle against the serrated labial plate, is succeeded by 

 twelve body-segments whereof the first and last bear- 

 paired false feet ai'med with circles of booklets. Special 

 breathing organs like the gills of a Chironomus-larva 

 are absent; this giaib evidently breathes the dissolved 

 air over the whole surface of the skin, a method of 

 respiration common among very small aquatic insects. 



Among the insects found by Mr. Eaton on Kerguelen 

 Island is a female midge which resembles Clunio in some 

 pai-ticulais. The body is elongate and worm-like, and 

 the wings ai'e reduced to small vestiges, but the legs 

 are relatively very long and the hind-body ends in a 

 pointed ovipositor (Fig. 11). This southern Chironomid 

 — Haliryfus amphihiiis is its name — was found " at the 

 verge of the tide, creeping over Enteromorplia and 

 mussels exposed by the recess of the sea. and walking 

 upon the siu-face of puddles and tide-pools. The fly was 

 common upon some small isolated rocks which were 

 always submerged at high water. The adults in that 

 locality must spend a large portion of their lives under 

 water. Probably whenever the water has retired 

 sufficiently from the top of the rocks, all tbe flies huiTy 

 up from below to take an airing." 



Another tiny marine midge (Fig. 10) has lately been 



Fi&. 10. 



Fig. 10. — Eretmoptera Brownii, male. 

 (Alter Kt'llogg.) 

 Fi&. 11. — Haliri/tiis amphibius. female. 

 (After Eaton.) 



4 

 Fig. 11. 

 Magnified 15 times. 



Magnified 12 times 



discovered on the rocky coast of California, and named 

 Eretmopfera Bruuni by Prof. Yenion L. Kellogg.§§ 

 On account of its very remarkable structiu-e its 

 describer considers it the type of a distinct family. In 

 both sexes the wings are " narrow and strap-like and 

 wholly without veins . . . not specially thin or 

 delicate, but rather thickened." The hind-wings, 

 instead of being the stalked knob-like " balancei-s " 

 usual among the Diptera, " are minute scale-like pro- 

 cesses appearing like rudiments ' of wings" of the 

 ordinary type. It is possible, therefore, that this midge 



§§ V. L. Kellogg. " An Extraordinary New Maritime Fly." 

 Biol. Sulletin, Tol. I., 1900, pp. 81-7. 



may represent a very early stage in the evolution of 

 the Diptera. before the characteristic " balancers " had 

 become specially modified. " The flies, of which there 

 were many, were resting or running on the surface of 

 the ocean water of tide-pools, and had a t.endency to 

 gather in large numbers in patches and in ball-like 

 masses on the water." The discovery of this most 

 remarkable midge shows what wonders of insect life 

 may still await the diligent observer by the sea^shore. 



Reviewing generally the marine flies here briefly 

 sketched, it will be noticed that they show a strong 

 tendency towai'ds the reduction or total loss of their 

 wings. It will be remembered that a similar tendency 

 is found among the marine beetles, but the flies are such 

 typically aerial insects that loss of flight among them 

 is especially remarkable. In a well-known passage 

 Dr. A R. Wallace||[| has pointed out that the insects 

 inhabiting oceanic islands are often flightless, and he ex- 

 plains this as due to the action of natiu-al selection ; when 

 flying individuals are liable to be blown out to sea, it 

 becomes a positive advantage to the species to lose the 

 power of flight. This state of things seems to be can-ied 

 to an extreme on the far-off wind-swept island of 

 Kerguelen. There can be little doubt that life by the 

 sea^shore is rendered safer for insects, when through loss 

 of the power of flight, they have ceased to expose them- 

 selves to the full power of the wind. And thus the 

 degi'adation which they have undergone is the price of 

 a more perfect adaptation to the strange surroundings 

 which their ancestors chose long ago. 



ROUND FAIR HEAD. 



By Grenville A. J. Cole, m.e.i.a., f.g.s. 



The north-east of Ireland is essentially the land of 

 Scots. From the third to the sixth century, its enter- 

 prising sons went forth, ran their light curraghs into 

 the harboius of North Britain, held their own in that 

 rugged counti-y, and gave their name to Scotland. In 

 the sixteenth centuiy, the MacDonnells of the Isles, 

 thirsting for a wder empire, returned to their ancient 

 homes in the valleys that cut the Antrim plateaux, and 

 sought to establish themselves amongst the Irish, who 

 had almost forgotten the relationship. These Scots, 

 indeed, had to win back the land which their ancestors 

 had forsaken, and they fonn a population between 

 Ballycastle and Cushendall, Scottish and distinct, still 

 presei^ving the old religion, which was common to all 

 at the time of their return. 



In the midst of their territory rises the promontoi-y 

 of Benmore, Fair Head, as the English have called 

 it, a worthy opponent to the great headland of Kintyre, 

 which faces it foui^teen miles away across the sea. 

 There is no more distinctive feature in the county of 

 Antrim than this sheer cliff-wall, with the rugged talus 

 at its foot, a buttress to the coast, a defiance to the 

 northern storms. 



From Ballycastle on the west to the woods of 

 Murloiigh Bay upon the east, the great crag dominates 

 the landscape. Its essential characters become best 

 revealed if we approach it from Ballycastle Bay. 



South of us, on the broad dome of Knocklayd (Cnoc- 

 leithid), we have an epitome of the most momentous 

 phases of the geological history of Co. Antrim. The 

 base of the hill consists of old micaceous schists, rocks 



nil A. R. Wallace. "Darwinism." 2nd Edition (pp. 105-6). 

 London, 1889. 



