As a result of complaints received from farmers as to the presence of parasitic worms in sheep, an attempt was made during the period October 1923 to September 1924 (inclusive) to ascertain the distribution and relative abundance of the more usual parasitic worms inhabiting the alimentary canal of sheep in North Wales. Regular collections were made from the following centres:—Pwllheli, Carnarvon, Bangor, Conway and Llandudno, with a few records also from Colwyn Bay, Bethesda, Menai Bridge and Denbigh. All the sheep examined were slaughtered for food purposes, practically the whole being obtained from slaughter houses. Almost all had grazed for considerable periods on the farms in the district mentioned, at elevations varying from sea level to 600 feet.

In some investigations on skin penetration by the filariform larvæ of Strongyloides (Goodey, 1925), the writer made use of larvæ cultivated from the droppings of a Guinea Baboon, Papio papio, which had died at the Gardens of the Zoological Society of London. Scrapings of the lining of the small intestine of this animal were made so as to secure the parasitic worms of which 25 specimens were obtained. A study of these was undertaken because von Linstow's (1905) original description of the species is so slender and his figures illustrating it are so crude that it was considered that the parasite would repay further investigation. Moreover one or two of his statements as, for example, that the cuticle of the parasite females is unstriated, required critical examination. Again in a recent paper Chandler (1925) has thrown doubt on the specific identity of S. fülleborni, suggesting that it is probably a hostal variety of S. papillosus. For these reasons the present paper has been prepared in that it gives a fuller account of S. fülleborni both in the parasitic and in the free-living generation than has hitherto been available. The writer considers that a detailed and well illustrated account of the morphology of S. papillosus, particularly of the free-living, sexual generation, is much needed at the present time.

Two species belonging to the Nematode genus Physaloptera have up to the present been reported from Man; P. caucasica v. Linstow, 1902, which has been obtained on one occasion only from the Caucasus, and P. mordens Leiper, 1908, which has been reported on several occasions from Man and Monkeys from Central Africa. Until quite recently the only account of the former species was that of v. Linstow, and from this it was quite plain that the two species were distinct. Schulz (1926), however, has had the opportunity of re-examining the types of P. caucasica and on the basis of his excellent descriptions and figures it is possible to make a closer comparison between it and P. mordens. Schulz was able to rectify several inaccuracies in v. Linstow's description, and he came to the conclusion that the two species were very closely related, the only difference between the two being that in P. caucasica there is in addition to the three large teeth on each lip also a series of small teeth between and exterior to them on the inner face of the lip, which teeth are absent in P. mordens; also that the former species was smaller than the latter, 14–24 mm. to 29–34 mm. for the male and 24 mm. to 41–100 mm. for the female respectively, and that the eggs of the former were larger.

The Ministry of Agriculture and Fisheries awarded the writer a special research grant to continue the investigation of the helminth parasites in the alimentary tract of sheep and other ruminants in North Wales.

In “An account of some helminthes contained in Dr. C. M. Wenyon's collection from the Sudan,” published in the Third Report of the Wellcome Research Laboratories at Khartoum, I drew attention in 1908 to the importance of the mouth armature of the Bursate Nematodes and suggested the regrouping of the various genera into three separate families: Strongylidæ, Metastrongylidæ and Eustrongylidæ. The Strongylidæ were divided into three and the Metastrongylidæ into two sub-families. Under the sub-families were listed the names of those genera which I then thought fell into each group, but to none did I append the name of the author or the date of the genus. The genus Protostrongylus occurred in the list of genera of Metastrongylinæ. Where, as in Trichostrongylinæ and Metastrongylinæ new names were suggested, these were indicated by the insertion of N.N. after each. Yet in two important compilations dealing with the classification of the Nematodes published during the present year the authors place on me the responsibility for proposing the generic name “Protostrongylus.” Thus in Baylis and Daubney, page 253, the name is listed Protostrongylus Leiper, 1908, and it is stated that “this name is mentioned by Leiper among genera attributed to his sub-family Metastrongylinæ. No species is mentioned and the name appears to be a nomen nudum.” Yorke and Maplestone similarly listed the genus Protostrongylus Leiper, 1908, among those genera insufficiently known and of uncertain systematic position, stating that it is one “belonging to the sub-family Metastrongy linæ.

Page 8, line 4, for Echinostomum read Echinostoma.

Page 9, line 2, for ancanthus read acanthus.

Page 12, line 8, for oligartha read oligarthra.

Page 19, Fig. 2, line 4 of legend, for c, d, and g, read c and d.

Page 75, line 9 from bottom, for parasite read parasitic.

Page 86, line 1, for wel read well.