Sudden phase anomalies produced by solar flares have been observed simultaneously on several long VLF propagation paths. The paths providing useful data are NBA (18 kc/s) Panama to Boulder, Colorado; to Maui, Hawaii; to Frankfort, Germany; and to College, Alaska; and GBR (16 kc/s) Rugby, England, to Boulder; and NPG (18.6 kc/s) Seattle to College, Alaska. The observations show that during a solar flare the magnitude of the mean change of reflection height Δh on each sunlit path can apparently be related to the mean of log sec χ along the path, where χ is the solar zenith angle. Different flares, however, produce different curves of Δh versus the mean of log sec χ. These results are discussed in terms of a layer produced below the normal height of reflection, and the energy (wavelength) and intensity (flux density) of the X rays that produced the new layer are estimated.

A comparison is made between the phase and amplitude of the 18‐kc/s signal NBA (Balboa, Panama) recorded at Boulder, Colorado, in the northern hemisphere and Tucumán, Argentina, in the southern hemisphere. Although these two propagation paths are essentially the same length, the difference between them in the diurnal change in phase height is approximately 5 km, and the estimated field strength appears to be significantly lower at Tucumán than at Boulder. It is suggested that the cause of these observed differences is the latitudinal variation in ionization due to cosmic rays.

additional information has been gathered as to their occurrence and distribution, and no connected account of these has as yet been published. During the same time, too, some important works on the Blind Subterranean Crustacea of other parts of the world have appeared, particularly Packard's work on the Cave Fauna of North America [83], and Wrzesniowski's very important memoir on "Three Subterranean Amphipoda" [124]. If we consider the peculiarities of the New-Zealand fauna and flora, and remember that New Zealand forms by itself a distinct zoological province, which has long been more or less perfectly isolated from other provinces, we should naturally expect that the Subterranean Crustacea of New Zealand would present us with some new interesting facts, and that they would differ largely from the similar Crustacea found elsewhere. This proves to be the case. The Subterranean Crustacean fauna is peculiarly rich, and much more varied than that of either Europe or North America ; so far as at present known, it consists of six distinct species, three Amphipods and three Isopods, l)clouging to five difi"erent genera. Of these genera Crangonyx is already known from the subterranean waters of Europe and North America, but none of the others have been recorded from underground habitats elsewhere, though one, Gammarm, is more or less allied to the blind Niphargm of Europe, the species of which were indeed originally assigned to Gammariis, and are still so assigned by some writers. Two genera are new : one, Cruregens, belongs to a family, the AnthuridcB, no members of which were previously known to inhabit underground waters, and the other, Phreatoicus, which now contains three species (two from the subterranean waters of New Zealand, and one freshwater one from the top of the Mt. Kosciusko plateau in Australia), is so peculiar that it forms the type of a new and very remai-kable family of the Isopoda. In the following pages I give a full detailed description of the external anatomy of each of these six species, in addition to the brief specific diagnoses and, usually, a discussion on the characters of the genus. I have given what is known of theu* occurrence and distribution, of their habits, and of the paculiarities which they present in common with or in addition to other Subterranean Crustacea ; their probable origin is discussed at some length. I have given also a short historical introduction showing the growth of our knowledge on the subject of Cave and Well Sessile-eyed Crustacea; and have concluded with some remarks on the bearing of the facts presented by them on the general questions of Biology. Eor their kindness in providing me with material, I have to record my best thanks to Mr. R. M. Laing, of the Christchurch Boys' High School, Mr. E. Wilkinson, of the School of Agriculture, Lincoln, Messrs.

For short periods of time during June and July of 1963 t he U.S. Navy t rans mitters located at Jim Creek, Wash. (NPG), and Balboa, Panama (NBA), simulta neo usly t ransmitted a frequency stabilized signal of 18 kc/s . The phase and relative amplit ud c of these s ignals were monitored at Boulder, Colo.; College, Alaska; lVlau i, H awaii ; and Tu cum{m, Argentin a. A sc mi e mpirical method by which the mean r elative phase velocity can be calculated from t he measurements of ph ase made at t hese four l"rcording s ites is demonstrated. The va lues of t he mean r elative phase velocity a t 18 kc/s w hi ch are obtain ed for daytime and nighttime propagation cond itions are resp ectively, (Vp / c)

THE first Terrestrial Isopoda clescribecl froiii S e w Zealand were tliosc given by DtLtIit * jii 1863, in his account of the Crustacea, collcctcd by thc United States Exploring Expedition ; in it he described and figured in considcrablc detail 7 species (including oiie clouhtfnl one), all of them from the northern part of Scm Zealand. In 1865 one or tn-o species were addcd by IIeller fin tlie rcport on the Crustacea of the Novara Expedition. I n 1576 Mr. E. J. Jfiers $ compiled a Catalogue of the New Zealaird Crustacea, ancl in connection therewith describcd soiiie new species that wcre in the collections of the British Musenru; hc added 5 specics, ancl his catalogue contains altogether 1 2 species and one considcred doubtful. Dwing subsequent years a few species i x r e acldcd by Jtr. G. 11. Tlionisoii 8 and inysclf 11, ttnd all the species knomn n-ere included in our " Critical List of the Crustaccs Jfalacostraca of Xew Zcalaiicl." 7 In 1885 B u d d c-L i d ** puhlislicd liis " Crustacca Isopoda Terrestria," ancl added two new species and meiitioncd most of tliosc previously described, hut as he was unable to examine specimens he could g i w no aclditional iuformation 011 them, and was obliged t o lem-e ser-era1 of t heiii uiider the licadiug of' " micertain specics.'' Four other nem species were described and figured by Filliol in 1883 in his " 3lission cle l'ile Campbell," f-fin which lie also grtve references to previously described species. I n the present papcr I endeavour to g i~e a coiiipletc list of all the New Zealand Terrestrial Isopoda at prcscnt known, with clcscriptions of the 1-arious species and figures where necessary. The material at illy disposal consists chiefly of collectioiis that I have accuiiiulated since 1S84. Besides specimens that I have collected myself, I have 111aiij-from Nr. R. llelms, formerly of Grcyniouth, Mr. J. 3lcJfahon, of Kenepuru,