The best of his books after this date are those written expressly for boys, the favourites being Masterman Ready (1841), The Settlers in Canada (1844), and The Children of the New Forest (1847).
Masterman's more detailed comparisons have for the most part been rejected by other morphologists.
Even if it be admitted that the postseptal space may be the metasomatic cavity, the praeseptal space can hardly be regarded as coelomic in nature, since it is in continuity with the vascular system; while Masterman's conclusion that the cavity of the praeoral hood (the supposed proboscis-cavity) is separated from that of the supposed collar has received no confirmation.
Regarding this as a collar-cavity, it becomes possible to agree with Masterman that the region shown in fig.
Since his time the duc de Luynes, Lartet, Wilson, Hull, Blanckenhorn, Gautier, Libbey, Masterman and Schmidt, to name but a few, have made contributions to our knowledge of this lake; but still many problems present themselves for solution.