In some species of the genus Cunina (Narcomedusae) the youngest individuals (actinulae) are parasitic on other medusae (see below), but in later life the parasitic From Allman's Gymnoblastic Hydroids, by permission of habit is abandoned.
- Tentaculocyst (statorhabd) ous with the endoderm of Cunina solnzaris.
- Tentaculocyst of Cunina lati- their simplest form as a ventris.
The direct type of budding is rare, but is seen in Cunina and Millepora.
In Cunina there arises, first, a simple outgrowth of both layers, as in a polyp-bud (fig.
The nearest approach to the phylogenetic sequence is seen in the budding of Cunina, where the manubrium and mouth appear first, but the umbrella is formed before the tentacles (fig.
In the indirect or coenogenetic method of budding, the first two members of the sequence exhibited by Cunina change places, and the umbrella is formed first, the manubrium next, and then the tentacles; the actual mouthperforation being delayed to the very last (fig.
II, Method of Cunina; (a) the mouth arises, next the umbrella (b), and lastly the tentacles (c).
Metchnikoff in Cunina and allied genera.
48), where it is ambulatory, in Gonionemus (Trachomedusae), and in Cunina (Narcomedusae), where it is parasitic.
Thus in Cunina octonaria, the ovum develops into an actinula which buds daughteractinulae; all of them, both parent and offspring, develop into medusae, so that there is no alternation of generations, but only larval multiplication.
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.
In the Leptolinae we must first substitute polyp for actinula, and then a condition is found which can be compared to the case of Cunina parasitica or Gonionemus, if we suppose that neither the parent-actinula (i.e.
In Cunina and allied genera the actinula, formed in the manner described, has a hypostome of great length, quite disproportionate to the size of the body, and is further endowed with the power of producing buds from a stolon arising from the aboral side of the body.
- Cunina rhododactyla, one of the Narcomedusae.
"' Vergleichend-embryologische Studien " (Geryoniden, Cunina), ibid.
A parasitic mode of life is also seen in medusae of the genus Cunina during the larval condition, but the habit is abandoned, in this case, when the medusae become adult.