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outside which was heavy blue sand and loam, and the space inside and over the urn was filled with small stones, about the size of walnuts, stained with white (which white stain I also found on some of the fragments of the larger urn).

The fragmentary state of the bottom of the urn, compared with the very perfect state of the mouth, would, I think, be accounted for by the fact of moisture lying on the bottom for such a lengthened period. So far as I have been able to discover, the larger urn is one of the most beautifully and richly decorated urns that has been found in Ireland. With the urns were found a large human skull and arm bones.

XXVI.

ON A NEW SPECIES OF EARTH-WORM.

HILDERIC FRIEND, F.L.S.

BY THE REV.

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THROUGH the courtesy of Dr. Scharff I received in the middle of June, 1892, a consignment of earth-worms collected in his garden in Dublin, which included, in addition to several species already well known to occur in Britain, one which is new to science. I have pleasure in submitting the following account of the new species under what seems to be its most fitting designation, the Irish worm (Allolobophora hibernica). I shall first deal with the general characters of the species, then give a detailed account of the specimens studied, and finally determine its position and relationships.

I. GENERAL CHARACTERS.

A. hibernica, sp. nov.

When living and extended in the act of crawling the worm (fig. 1) is about 2 inches or 50 mm. in length. In spirits it is from 1 to 1

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inches, or 25 to 35 mm. long, and thus ranks in size with three or four of our British dendrobænic worms, such as the tree-worm (A. arborea, Eisen), or the Celtic worm (A. celtica, Rosa). Unlike these, however, its colour is fleeting, so that immediately upon being placed in alcohol the small quantity of colouring matter which is present in the living worm evanesces, leaving the preserved animal without the least indication of its pretty appearance in a state of nature. The anterior portion of the worm when alive is of a rosy hue closely approaching flesh-colour; the girdle is a dull yellow, while the rest of the body, excepting the caudal extremity, is a greyish hue, appearing brown along the line of the dorsal vessel. The last half dozen segments are yellow, just as in the gilt-tail or cockspur of the

angler (A. subrubicunda, Eisen). The presence of a pigment which is exuded from the dorsal pores accounts for this yellow tinge, which in the most adult specimens may be found pervading other portions of the body to a slight degree.

As regards the colour, therefore, this worm most closely resembles the mucous worm (A. mucosa, Eisen). The disposition of the setæ, however, settles the point of specific difference in a moment; for while the setæ of the mucous worm are arranged in four couples, the individuals of which are pretty close together, those of the Irish worm are in eight rows (fig. 8), more or less equidistant, as in the gilt-tail or the dendrobænic group.

With a worm so short as this it is rather unexpected to find so many segments, but the average is 90-100, so that they are very narrow, and closely arranged side by side. In this respect they come very near the constricted worm (A. constricta, Rosa).

The worm is a true Allolopobhora in the sense in which all modern writers, following the classification of Eisen, understand the term. In the genus Lumbricus the lip or prostomium (pr.) so completely cuts the first segment or peristomium (per.) as to form with it a perfect mortise and tenon. (See fig. 3.) The setæ, also, in Lumbricus, are always in four pairs (fig. 7), the individuals of which very closely approximate, and the colour is a warm ruddy brown with There are an iridescent colour-play under the action of light. other characters, both external and internal, which might be stated; but Allolobophora differs chiefly in the following points. The lip only cuts the peristomium partially, if at all (fig. 2); the setæ may be in pairs or scattered, while the colour is exceedingly variable. So far as British species go we find that in Lumbricus there are invariably six girdle segments, the inner four of which are (fig. 4) spanned by the puberty band (tubercula pubertatis), whereas in Allolobophora the girdle covers from five to eight or ten segments, and has the tubercula, if present at all, either on consecutive or alternate segments, in the shape of a band or as pores (see fig. 5), and varying in number from two upwards.

In the light of this brief statement of generic differences it will clearly be seen, when I state the distinguishing features, that the new worm belongs to the genus Allolobophora, and not to Lumbricus. The lip or prostomium is very small and pallid, not perceptibly cutting the first segment. When fully extended, however, the prolongation backwards into the peristomium may be distinguished for a short distance, owing to the extreme delicacy and whiteness of the lip, and

its attachment. When retracted the lip is quite closed by the peristomium, and lies in the buccal cavity unperceived from above. The setæ are scattered, and the colour, as already stated, is not of that permanent character which pertains to the Lumbrici. The latter genus is not represented by a single species which exudes a coloured or turbid secretion, whereas this animal, like the mucous and gilttail worms is wont to throw out a small quantity of fluid of a yellowish

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colour. Many other species belonging to this genus possess a similar property, and as the quantity of fluid discharged from the dorsal pores seems to vary with the maturity of the worm I am disposed to hold that it has something to do with the most important functions of nature. The position of the first dorsal pore has yet to be determined. In the mucous worm it can be readily seen, not so here.

The male pores are found on each side of the fifteenth segment (fig. 5 m.p.), being easily recognised in adult specimens by the small

papillæ upon which they are seated. In some worms bearing a close relationship to this species the papillæ are so large as to affect the two adjoining segments (14-16), but, in this case, no such prominent position is held by them. The girdle is conspicuous, dense, and closely fused on the dorsal surface, but each segment is clearly defined beneath. It covers six to eight segments, two only of which bear the tubercula pubertatis. The general outline of the girdle ventrally closely resembles that of the nearly allied mucous worm (A. mucosa, Eisen), as it is truthfully pourtrayed by Eisen in the plate which accompanies his original description. We shall the better understand this after studying the details supplied in the next section.

One rather striking peculiarity may here be emphasized. In several species of worms, such as the brandling (A. fœtida, Sav.), the long worm (A. longa, Ude), and the common earthworm (Lumbricus terrestris, L.), we find a tendency on the part of those segments which contain the sexual organs to become tumid and pale on the ventral side. In this case, however, it is the dorsal surface which is so affected, especially in segments 10 and 11, and on the worm being dissected the cause of this unusual appearance is at once discovered. Whereas in most species of worms the spermathecæ are ventrally or laterally placed, in the Irish worm they are disposed on the back.

II. SYSTEMATIC ACCOUNT OF SPECIMENS.

I was fortunate enough to find eight specimens of this worm in the batch consigned to me, and had recognised the novelty of the worm as soon as the first specimen or two had been transferred to alcohol, so that I was able deliberately to study the whole series, first in a living state, and afterwards in spirits. I have since received two large series of the same worm from Dr. Scharff, by means of which I have been able to confirm and extend my earliest observations. As the characters by which the species is distinguished in a living condition have now been generally set forth, I will proceed to specify some details respecting the individual specimens as they appear when preserved in alcohol. Not one of the specimens carried spermatophores, but six out of the eight were sexually mature, and the other two were in a specially good condition for external diagnosis. One of the most important points in relation to the classification of worms is that which concerns the number and position of the tubercula pubertatis and it frequently happens that the exact solution of the difficulty is accomplished with the greatest ease when the worms are in a state of puberty. Earlier in life there is absolutely nothing to differentiate one segment from

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