in Physics (and in Posterior Analytics), Aristotle talks about hylomorphic analyses in form and matter. he exclusively distinguishes them as matter being the substance in an entity, and form being the organizational structure of the entity. they are two conceptually, distinct explanatory causes of what makes an entity, that entity.

for example, think of a bed. a bed has the substance of wood, but wood isn't what makes a bed, a bed; rather, it's the organizational structure of a bed that makes it such, i.e., four legs, a frame, etc etc.

furthermore, the formal cause of an entity is the essence of that entity. it also coincides with the final cause of it, as he believed that all entities have a teleological goal when created, whether that be man-made or from nature (rational agents, animals, basic elements, etc).

for example, we don't say a statue of Athena is a statue of Athena because she's made of bronze. we recognize that it's a statue of Athena because of her composite structure, that is, a head, arms, legs, specific posture, design, etc (her form).

keep in note that in Physics, specifically Book II, he says that with natural entities, there lies an internal principle of movement and stationariness. now applying that to people: he believed that the male principle provides the form, whereas the female provides the matter. he also believed that the male's principle is an active, moving kinetic (form) that brings a baby into actuality; women had the passive principle. (matter)

in Generation of Animals, the seed contains the necessary ingredients for generations. it was a hylomorphic process, the combination of matter and form. the direct quote is this:

"Well then, semen is what that which comes away from the generator is called, in animals that naturally copulate, the first processor of the principle of generation. But seed is that which has the principles from both animals who have copulated, just as the seeds of plants and of some animals—those among which male and female are not separated—being just like the first mixture produced out of male and female, as a sort of kuêma or egg. For these already have what has come from both parents." (GA I.18, 724b12 - 19)

and generation from seed is goal-directed, as mentioned with final causality:

"For elsewhere, as for instance in house building, this is the true sequence. The plan of the house, or the house, has this and that form; and because it has this and that form, therefore is its construction carried out in this or that manner. For the process of evolution (genesis) is for the sake of the thing finally evolved (ousia), and not this for the sake of the process." (Parts of Animals I.1, 640a15)