PERE eG ESTES Cie MGT 5 etee Oe ees CUO ea eRe eet Nea rae Ee 
Bucuanan.—On Pseudo-scab and Lung-worm in Sheep. 269 
The only other species of Neritina recorded from New Zealand is N. 
zealandica, Reclwz., P.Z.S., 1845, p. 120; but it appears doubtful if the 
specimens were actually procured in this country. 
Those now under consideration were found among the debris brought 
down by the Waikanae River; probably if the stream were carefully 
examined further up living examples might be procured, and it is important 
that this should be done, in order that the animal may be described as well 
as the shell. A considerable number of specimens were obtained, and sub- 
mitted to careful examination, yet although there are minor points of 
difference, the general characters agree so well with the description of N. 
Jluviatilis that I am obliged to refer it to that species. Probably, however, the 
animal when discovered will exhibit sufficient distinctive characteristics to 
warrant the foundation of a new species. 
Art. XXXVIII.—0On Pseudo-scab and Lung-worm in Sheep. 
By Joun Bucuanan, F.L.S. 
[Read before the Wellington Philosophical Society, 6th August, 1881.] 
Pseudo-scab in sheep. 
A piszase in sheep resembling Acari Scab, having recently attracted 
attention among flock-owners, several pieces of affected skin were forwarded 
by the Sheep Department to the Museum for examination and report, but 
with no definite results, in consequence of the disease in every case having 
reached its crisis and the wool having again begun to grow, and only in 
one case was it clear that the skin had been burrowed by worms. 
The conclusions arrived at in lung-worm disease, regarding the life- 
history of the lung-worm (Strongylus filaria), are clearly applicable in the 
Present case, and it is also highly probable that the same species or an 
allied one produces this eruption on the sheep, the eruption disappearing 
in autumn, after which the sheep regain their usual health. The conditions 
most favourable to the selection of the skin as a nidus, are wet seasons, 
When the sheep are ina continually soaking condition from rain; such 
Weather is also favourable to the movements of the young worms when in 
Search of a host. 
It is doubtful whether the worms in every case burrow sie thar: a3 
n0 doubt the clotted secretions of yolk at the base of the wool offer sufficient 
in many eases ; it is certain, however, that a scab is produced in 
sat a Chane Sie arena ae ets De nt and their 
ere ce 2 
Vine im end 
se 
ee 
