APPENDIX.--On various occasions I have dwelt upon the necessity of acquiring accurate information respecting the degree of mortality due to parasites, and in the present volume (p. 124) I have referred to the defective evidences supplied by the returns of the Registrar-General in respect of the echinococcus disease. My object is not to cast blame upon those whose duty it is to publish the returns, but rather to call attention to the advantages that would follow if the Registrar-General were supplied with full and accurate information on this head. Through the courtesy of Mr Noel A. Humphreys I have been furnished with the following official statement of the number of _Deaths from Worms_ in England and Wales, as recorded in the Annual Reports of the Registrar-General throughout a decade of years: +--------------+----+----+----+----+----+----+----+----+----+----+ | |1868|1869|1870|1871|1872|1873|1874|1875|1876|1877| +--------------+----+----+----+----+----+----+----+----+----+----+ |Total | 172| 148| 151| 160| 154| 183| 188| 227| 204| 225| | including-- +----+----+----+----+----+----+----+----+----+----+ |Porrigo | 15 | 13 | 9 | 9 | 9 | 14 | 5 | 16 | 7 | 13 | |Scabies | 6 | 2 | 7 | 1 | 4 | 2 | -- | 5 | 2 | 3 | |Tapeworm | 8 | 3 | 6 | 3 | 5 | 3 | 5 | 5 | 2 | 6 | |Hydatids | 20 | 20 | 33 | 37 | 41 | 34 | 29 | 43 | 31 | 51 | +--------------+----+----+----+----+----+----+----+----+----+----+ Considering the prodigious advances in helminthology during the last half century, it is certainly remarkable that under the category of “worms,” as a cause of death, only two kinds of true helminths should be mentioned in the Registrar’s record. It will also strike the experienced hospital and dispensary physician as somewhat remarkable that of the two death-producing parasites above named one of them should be the “tapeworm.” Now death from _Tænia_ is certainly a very rare occurrence, although grave nervous symptoms are not unfrequently due to its presence in man. Thus, I am inclined to regard the 46 reported instances of death from this cause as a redundant estimate. On the other hand, I am surprised to see no specified instances of death from lumbricoid Ascarides, from Oxyurides, or even from Cysticerci, which now and then take up their residence in the human brain.