Similarly bud-scales can be caused to develop into foliage-leaves, if the buds to which they belong are caused to grow out in the year of, their formation by the removal of the existing foliage-leaves.
- The formation of buds which separate to form new cells.
The food of this species seems to consist of the seeds and buds of many sorts of trees, though the staple may very possibly be those of some kind of pine.
In the first place, buds may be produced only from the hydrorhiza, which grows out and branches to form a basal stolon, typically net-like, spreading over the substratum to which the founderpolyp attached itself.
In the second place, the buds may be produced from the hydrocaulus, growing out r-y:.
12, 14) the founder-polyp is, theoretically, of unlimited growth in a vertical direction, and as it grows up it throws out buds right and left alternately, so that the first bud produced by it is the lowest down, I he second bud 15 above the first, the third above this again, and so on.
15),the polyps produce buds right and left alternately, so that the hydranths are arranged in a zigzag fashion, forming a " scorpioid cyme," as in Obelia and Sertularia.
Buds may be produced from the manubrium, radial canals, ring-canal, or tentaclebases, or from an aboral stolon (Narcomedusae).
In any case the daughter-individuals produced from the buds may be imagined as remaining attached to the parent and forming a colony of individuals in organic connexion with one another, and thus three possible cases arise.
It is convenient to distinguish buds that give rise to polyps from those that form medusae.
The 'ej: ¦ buds that form polyps ?
The buds of Margellium are produced on the manubrium in each of the four interradii, and they arise from the ectoderm, that is to say, the germinal epithelium, which later gives rise to the gonads.
The buds do not appear simultaneously but successively on each of the 1 four sides of the manubrium, thus: 3 4 and secondary buds.
2 may be produced on the medusa-buds before the latter are set free as medusae.
In Cunina parasitica, however, the ovum develops into an actinula, which buds actinulae as before, but only the daughter-actinulae develop into medusae, while the original, parent-actinula dies off; here, therefore, larval budding has led to a true alternation of generations.
A " stolon " of unknown origin produces thirty-two buds, which become as many Polypodia; each has twenty-four tentacles and divides by fission repeated twice into four individuals, each with six tentacles.
B, The long manubrium, bearing medusiform buds; a, mouth.
It buds medusae, which, however, are as yet only known in an immature condition (C. Mereschkowsky ).
The medusae, on the other hand, have the tentacles in four tufts of (in the buds) five each, and thus resemble the medusae of the family Margelidae.
The medusa-buds, as already stated, are always produced from blastostyles, reduced non-nutritive polyps without mouth or tentacles.
In A two medusa-buds are seen within the gonotheca (gth), the upper more advanced than the lower one.
Manubrium and In C the marsupium (m) is formed as finger-like another below the process from the summit of the blastostyle, en closing the acrocyst; b, medusa-buds on the radial canal in blastostyle.
Obelia forms numerous polyserial stems of the characteristic zigzag pattern growing up from a creeping basal stolon, and buds the medusa of the same name.
Each corbula contains a central row of blastostyles enclosed and protected by lateral rows of branches representing stunted buds (Allman , p. 60, fig.
This is in some degree parallel to the cases described above, in which a planula gives rise to the hydrorhiza, and buds a polyp laterally.
At the same time it produces buds from an aboral stolon.
The buds become medusae by the direct method of budding described above.
In some cases the buds do not become detached at once, but the stolon continues to grow and to produce more buds, forming a " bud-spike " (Knospencihre), which consists of the axial stolon bearing medusa-buds in all stages of development.
Cunoctantha fowleri Browne, buds are formed from the sub-umbrella on the under side of the stomach pouches, where later the gonads are developed.
In the same tanks a small hydroid, very similar to Microhydra, has been found, which bears medusa-buds and is probably the stock from which the medusa is budded.
It buds medusae from the margin of the mouth in May and June, and in August and September the gonads' are formed in the place where the buds arose.
The buds and ieaves on the exposed side are probably killed by sand blasts.
The Vertebrata come within the scope of our subject, chiefly as destructive agents which cause wounds or devour young shoots and foliage, &c. Rabbits and other burrowing animals injure roots, squirrels and birds snip off buds, horned cattle strip off bark, and so forth.
Grapholitha) eat the buds or the roots (e.g.
They may occur on all parts, buds, leaves, stems or roots, as shown by the numerous species of Cynips on oak, Phylloxera on vines, &c. The local damage is small, - but the general injury to assimilation, absorption and other functions, may be important if the numbers increase.
Bruising by a cartwheel, insects-having started a callus on which adventitious buds arise, or to the destruction of buds at an early stage.
Then, stores of food-material being accumulated at the injured place, other buds arise at the base of or around the injured one.
The hind limbs appear as buds at the base of the tail, and gradually attain their full development during the tadpole life.
Long; it is found in New England and the milder parts of Canada, and is frequently planted in Britain; its growth is extremely rapid in moist land; the buds are covered with a balsamic secretion.
In these northern habitats it attains a large size; the wood is very soft; the buds yield a gum-like balsam, from which the common name is derived; considered valuable as an.
Chun and Woltereck, on the other hand, regard the stem as a stolo prolifer arising from the aboral pole, that is to say, from the ex-umbrella, similar to that which grows out from the ex-umbral surface of the embryo of the Narcomedusae and produces buds, a view which is certainly supported by the embryological evidence to be adduced shortly.
Woltereck considers the siphonophores most nearly allied to the Narcomedusae, producing like the buds from an aboral stolon, the first bud being represented by the pneumatophore or protocodon, in different cases.