we are led to believe that the stems of this Ceratophyllum circumnutate, probably in the shape of narrow ellipses, each completed in about 26 h.  The following statement, however, seems to indicate something different from ordinary circumnutation, but we cannot fully understand it.  M. Rodier says:  “Il est alors facile de voir que le mouvement de flexion se produit d’abord dans les mérithalles supérieurs, qu’il se propage ensuite, en s’amoindrissant du haut en bas; tandis qu’au contraire le movement de redressement commence par la partie inférieur pour se terminer a la partie supérieure qui, quelquefois, peu de temps avant de se relever tout à fait, forme avec l’axe un angle très aigu.”

(18.) Coniferae.—­Dr. Maxwell Masters states (’Journal Linn.  Soc.,’ Dec. 2nd, 1879) that the leading shoots of many Coniferae during the season of their active growth exhibit very remarkable movements of revolving nutation, that is, they circumnutate.  We may feel sure that the lateral shoots whilst growing would exhibit the same movement if carefully observed.

* ‘Comptes Rendus,’ April 30th, 1877.  Also a second notice published separately in Bourdeaux, Nov. 12th, 1877. [page 212]

(19.) Lilium auratum (Fam.  Liliaceae).—­The circumnutation

Fig. 83.  Lilium auratum:  circumnutation of a stem in darkness, traced on a horizontal glass, from 8 A.M. on March 14th to 8.35 A.M. on 16th.  But it should be noted that our observations were interrupted between 6 P.M. on the 14th and 12.15 P.M. on the 15th, and the movements during this interval of 18 h. 15 m. are represented by a long broken line.  Diagram reduced to half original scale.

of the stem of a plant 24 inches in height is represented in the above figure (Fig. 83).

Fig. 84.  Cyperus alternifolius:  circumnutation of stem, illuminated from above, traced on horizontal glass, from 9.45 A.M.  March 9th to 9 P.M. on 10th.  The stem grew so rapidly whilst being observed, that it was not possible to estimate how much its movements were magnified in the tracing.

(20.) Cyperus alternifolius (Fam.  Cyperaceae.)—­A glass [page 213] filament, with a bead at the end, was fixed across the summit of a young stem 10 inches in height, close beneath the crown of elongated leaves.  On March 8th, between 12.20 and 7.20 P.M. the stem described an ellipse, open at one end.  On the following day a new tracing was begun (Fig. 84), which plainly shows that the stem completed three irregular figures in the course of 35 h. 15 m.]

Concluding Remarks on the Circumnutation of Stems.—­Any one who will inspect the diagrams now given, and will bear in mind the widely separated position of the plants described in the series,—­remembering that we have good grounds for the belief that the hypocotyls and epicotyls of all seedlings circumnutate,—­not forgetting the number of plants distributed in the most distinct families which climb by a similar movement,—­will