A special study of the relation of cases of copious hæmoptysis to different forms of heredity has been made by Reginald Thompson. His table is as follows:
COPIOUS HÆMOPTYSIS.
| Age at which attack commenced. | ||||||||||||||
| Cases. | 5 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 | 65 | |
| Mother | 123 | ... | ... | 27 | 30 | 34 | 18 | 8 | 2 | 3 | 1 | |||
| Father | 102 | 1 | 4 | 16 | 22 | 24 | 19 | 9 | 4 | 1 | ... | 1 | 1 | |
| Non-hereditary | 105 | ... | 2 | 14 | 20 | 24 | 16 | 12 | 8 | 5 | 2 | |||
He claims that this table shows that of the cases of direct heredity, cross-heredity, and non-heredity, those who were the subjects of cross-heredity—that is, those from the mother—were more liable to copious hæmoptysis than either the cases of direct heredity or of non-heredity; and the numbers of the two latter so closely correspond as to show that heredity from the father has little influence as regards hemorrhage. The conclusion he draws from the table is that "an heredity is drawn from the mother which differs from that derived from the father, and to this must be attributed the excess of cases of copious hæmoptysis."
This difference will be seen in the following table, which shows the number of cases occurring before and after thirty:
| Cases. | Before age of 30. | After age of 30. | |
| Mother | 123 | 91 | 32 |
| Father | 102 | 65 | 37 |
| Non-hereditary | 105 | 60 | 45 |
He thinks the explanation is to be obtained from the statistics of hæmophilia, which show a large proportion of transmissions from mothers to sons, and that we have here a strong argument connecting copious hæmoptysis, not with tubercle, but with hæmophilia.
His next table is one of 125 cases of double heredity, calculated upon the same basis as the others, that of 400:
| Cases. | 5 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 | 65 | |
| Double heredity | 125 | ... | 3 | 20 | 40 | 23 | 15 | 12 | 9 | 1 | 1 | 1 | ||
| Calculated to | 400 | ... | 10 | 74 | 128 | 75 | 48 | 37 | 29 | 3 | 3 | 3 | ||
which shows a close approximation to the table of cases of cross-heredity from the mother, and that the calculated number for 400 cases of double heredity are almost identical with that of the actual number of 400 cases of cross-heredity between the ages of fifteen and twenty-five—in the first case being 202, in the second 203—and the calculated number of cases before thirty amount to 287, not quite equal to actual number for cases of cross-heredity, which is 294. He concludes that these cases do not show a greater tendency to hemorrhage than is shown in cases of direct and non-heredity. We may accept these figures and calculations as important without endorsing the conclusion which they are intended to sustain—viz. that such hæmoptyses are essentially of hæmophilic origin. It may be stated as a general opinion that hæmophilia does not especially manifest itself in pulmonary hemorrhages, and that hæmophilic families are not specially liable to phthisis.