From considerations of previous work on the vinegar eelworm, and from the writer's experiments, it is concluded that:

I.—Concerning physical and chemical stimuli:

(a) The worm has very little need of oxygen, but displays a negative geotaxis which is independent of dissolved oxygen as a stimulus.

(b) It tolerates temperatures between 0° and 35°, can survive short intervals at 20°, and can live for several days at 37°. It is practically indifferent to light.

(c) The worm and its larvæ are very susceptible to drying, surviving only a few minutes a thorough desiccation from water.

(d) The toleration limits for hydrogen ion concentration are pH: 1·6 on the acid side and about pH : 11 on the alkaline side.

(e) So far as can be ascertained, the worm tends to make the medium in which it lives slightly but permanently more acid than it would otherwise be.

(f) It is very sensitive to iodine, ammonia and chloroform, but is extraordinarily resistant to most chemical substances, including acidity indicators and buffer solutions.

(g) It can be grown in most culture media, and has been cultured aseptically by Zimmermann, who finds that either bacteria (living or dead) or an unknown substance from the autolysate of yeast is essential as food.

Heterodera schachtii Schmidt, 1871, first discovered and studied by Schacht in 1859 was recognised as a parasite injurious to the sugar-beet by Ktihn in 1881. Subsequent to the discovery of its pathogenicity it has been studied by many observers both in Europe and in the United States where it was introduced about the beginning of the present century, and has now become established in the beet-growing areas of Utah and California. A detailed morphological account of the nematode was first given by Strubell, 1881, who carried out his observations on material obtained from sugar-beet. Other workers have supplemented Strubell's description in several minor respects and have also described the nematode as it occurs on other plant species.

In connection with investigations of the United States Bureau of Fisheries in Alaska in 1906, Professor H. B. Ward spent considerable time in the study of the parasites of the Pacific salmon. Around Excursion Inlet he secured a large amount of valuable material. The following study was made of one of the specimens collected by him, to whom I am grateful for the loan of it.

Last Fall my attention was called to an adult Necturus maculosus Raf. in our vivarium by Dr. C. L. Parmenter, in charge, from the cloaca of which protruded some mature tapeworm segments. One cestode only was found in the duodenum which measured 83 mm. The head was easily recovered. It proved to be Ophiotænia lönnbergii (Fuhrmann) as described and illustrated by La Rue (1914). La Rue has frequently found the species in Necturus from Ohio and Indiana. This one is from Allegheny in Pennsylvania, showing a wider distribution. La Rue states: “I have examined your slides of Ophiotænia from Necturus and find them to be O.lōnnbergii without question.”

Upon unanimous recommendation by the International Commission on Zoological Nomenclature, the International Zoological Congress which met at Budapest, Hungary, September 4th to 9th, 1927, adopted a very important amendment to article 25 (Law of Priority) which makes this article, as amended, read as follows (italicized type represents the amendment roman type represents the old wording):—