188 



KNOWLEDGE. 



[August, 1902. 



The Eucliolatii cmiiprise three families which all have 

 the first ii|)|)('ii(Iaf,'cs well developed l)ut vary in n>gard to 

 the second. Tiiese are wanting' in the Plioxichilidiidio, 

 small or nidimeutary in tlie Phoxichilidii-, and only Bve-to- 

 s.'vi'n-jniiit.Ml ill tlie Nymiilioiiidae. Tlie first of thi'se 



Nt/mphon hamatum, Hoek, i . Ventral view, legs only partially 

 shown. From Hoek. 



families has a further link with the preceding section in 

 that the females are without the ovigerous legs. Among 

 other genera it contains one to which the eecentric French 

 naturalist Eugene Hesse applied the name Oomerus, 

 meaning "eggs in the thighs." As Goldsmith said of 

 Edmund Burke that he " gave to a party what was meant 

 for mankind," so here the French writer allots to a single 

 genus a term that fits all the Pycnogonida. Very 

 probably his ill-defined genus is not distinct from the 

 earlier Phoxichilidium, Milne-Edwards, 1840, from which 

 Wilson, in 1878, separated Anoplodactylus, itself perhaps 

 identical with Jnaphia, Say, 1821. In Phoxichilidium 

 the peculiarity has been noticed that the young become 

 parasitic on zoophytes. Anoplodactylus by its name, 

 meaning "unarmed finger," alludes to a supposed con- 

 trast between this genus and that from which it was 

 detached. The ambulatory legs in Phoxichilidium have a 

 powerful finger or claw, on the back of which close to the 

 base are a jmir of auxiliary claws, small but conspicuous. 

 A sjjecies which seemed to be without these accessories 

 was on that account transferred to Anoplodactylui', but 

 now in turn Sars has shown that the auxiliary claws are 

 actually present in the new genus as well as the old, 

 though so small and feeble as scarcely to deserve the title 

 of weapons. 



Of the Phoxichilidiidae some illustrations have been given 

 in earlier chapters. To it belong, in addition to genera 

 already mentioned, Pseudoimllcm,'W'\\son, 1878, Hannonia, 

 Hoek, 1881, Ne<>i>ollcne, Dolirn, 1881, Cordijlochele, Sars, 

 1888, and Pampallene. Carpenter, 18;>2. 



The Nynii)honidaj are interesting in various ways. As 

 already explained, Nijmphon marinitm (Strom) is the 

 earliest recorded species. Nijniphoii, Fabricius, 179i, is 

 the earliest genus but one, and includes a greater number 

 "f species than any of the other genera. Some of the 

 forms comprised in it, though not actually the largest, 

 are among the largest known. With one exception, 

 representatives of it reach the greatest depths in the 

 ocean attained by any of this group, descending a long 

 way below two thousand fathoms, so as to be separated 

 from the upper air by a thickness of two and a half miles 

 of water. The species figured was dredged up from one 

 thousand six hundred fathoms in the Southern Ocean. 

 Strom's N. marinun is one of six species of the genus found 

 in British waters. This was re-described by Harry 

 Goodsir in 1845 as N. gigantetan, from Northumberland. 

 He gives the span of it as six inches, equivalent to one 

 hundred and fifty millimetres. Other authorities give 

 the length of the body as three-fifths of an inch or fifteen 

 millimetres, so that the legs are nearly five times as long 

 as the body. But that this giant is not very corpulent is 

 shown by a further minute calculation which Kroyer 

 supplies. He reckons that the legs are about sixty times 

 as long as the breadth of their fourth joint, which no 

 doubt he chooses as being the limb's broadest part Till 

 recently a seventh British species of this genus might 

 have been counted, but Goodsir's N. spinosnm has now 

 been transferred by Sars to a new genus Ghxtohymphon, 

 "the hairy Nymphon." This designation alludes to a 

 characteristic which had been noted in three species, 

 respectively named on that account hirtum, hirtipes, and 

 spinosuni (shaggy, shaggy - foot, and thorny), by 

 Fabricius, Bell, and Goodsir. Besides five northern species 

 this genus contains one from the chill southern waters of 

 Kerguelen Island. The hairiness of this sub-antarctic 

 form is attested by the name hispidum given it by Hoek 

 in 1881, and by the earlier horridum given it by Bobm in 

 1879. But, let the species be as rugged as a bear, as 

 bristly as the fretful porcupine, it cannot retain either of 

 these names, for it has proved to be an acquisition made 

 by the Antarctic Expedition under Sir James Boss when, 

 visiting Kerguelen in May and June, 1840, an acquisition 



,,^ 



Chieluniimphon spinosum (G'Oodsir)'f . After Sars. 



which had lain in our national collection unnamed and 

 unregarded until a preliminary descrii)tion of it as Nijm- 

 phon brevicaudalum was published by Micrs in 1875. For 

 the Arctic sjiecies named by Bell Xijmphon robustuni, Sars 

 has founded the genus lioreimymnhnn, "the boreal 



