actinula

In zoology|lang=en terms the difference between planula and actinula

is that planula is (zoology) the larva of a hydrozoan, which is free-swimming and covered in cilia while actinula is (zoology) a kind of embryo of certain hydroids (tubularia), having a stellate form.

As nouns the difference between planula and actinula

is that planula is (biology) in embryonic development, a vesicle filled with fluid, formed from the morula by the divergence of its cells in such a manner as to give rise to a central space, around which the cells arrange themselves as an envelope; an embryonic form intermediate between the morula and gastrula while actinula is (zoology) a kind of embryo of certain hydroids (tubularia), having a stellate form.

As nouns the difference between terms and actinula

is that terms is while actinula is (zoology) a kind of embryo of certain hydroids (tubularia), having a stellate form.

As nouns the difference between actinula and actinulae

is that actinula is a kind of embryo of certain hydroids (Tubularia), having a stellate form while actinulae is plural of actinula.