Yes. The sensitive appetite is one generic power, and is called sensuality; but it is divided into two powers, which are species of the sensitive appetite -- the irascible and the concupiscible, because the concupiscible power regards both what is suitable and what is unsuitable, but the object of the irascible power is to resist the onslaught of the unsuitable.
Appetitus sensitivus est una vis in genere, quae sensualitas dicitur; sed dividitur in duas potentias, quae sunt species appetitus sensitivi, scilicet in irascibilem et concupiscibilem quia vis concupiscibilis est et convenientis et inconvenientis, sed irascibilis est ad resistendum inconvenienti quod impugnat.
As in the apprehensive powers of the sensitive part there is an estimative power, which perceives those things which do not impress the senses, as we have said above (Q78, A2); so also in the sensitive appetite there is a certain appetitive power which regards something as suitable, not because it pleases the senses, but because it is useful to the animal for self-defense: and this is the irascible power.
Sicut in apprehensivis virtutibus in parte sensitiva est aliqua vis aestimativa, scilicet quae est perceptiva eorum quae sensum non immutant, ut supra dictum est; ita etiam in appetitu sensitivo est aliqua vis appetens aliquid quod non est conveniens secundum delectationem sensus, sed secundum quod est utile animali ad suam defensionem. Et haec est vis irascibilis.
In order to make this clear, we must observe that in natural corruptible things there is needed an inclination not only to the acquisition of what is suitable and to the avoiding of what is harmful, but also to resistance against corruptive and contrary agencies which are a hindrance to the acquisition of what is suitable, and are productive of harm.
Ad cuius evidentiam, considerari oportet quod in rebus naturalibus corruptibilibus, non solum oportet esse inclinationem ad consequendum convenientia et refugiendum nociva; sed etiam ad resistendum corrumpentibus et contrariis, quae convenientibus impedimentum praebent et ingerunt nocumenta.
Therefore, since the sensitive appetite is an inclination following sensitive apprehension, as natural appetite is an inclination following the natural form, there must needs be in the sensitive part two appetitive powers--one through which the soul is simply inclined to seek what is suitable, according to the senses, and to fly from what is hurtful, and this is called the concupiscible: and another, whereby an animal resists these attacks that hinder what is suitable, and inflict harm, and this is called the irascible. Whence we say that its object is something arduous, because its tendency is to overcome and rise above obstacles.
Quia igitur appetitus sensitivus est inclinatio consequens apprehensionem sensitivam, sicut appetitus naturalis est inclinatio consequens formam naturalem; necesse est quod in parte sensitiva sint duae appetitivae potentiae. Una, per quam anima simpliciter inclinatur ad prosequendum ea quae sunt convenientia secundum sensum, et ad refugiendum nociva, et haec dicitur concupiscibilis. Alia vero, per quam animal resistit impugnantibus, quae convenientia impugnant et nocumenta inferunt, et haec vis vocatur irascibilis. Unde dicitur quod eius obiectum est arduum, quia scilicet tendit ad hoc quod superet contraria, et superemineat eis.
Now these two are not to be reduced to one principle: for sometimes the soul busies itself with unpleasant things, against the inclination of the concupiscible appetite, in order that, following the impulse of the irascible appetite, it may fight against obstacles.
Hae autem duae inclinationes non reducuntur in unum principium, quia interdum anima tristibus se ingerit, contra inclinationem concupiscibilis, ut secundum inclinationem irascibilis impugnet contraria.
Wherefore also the passions of the irascible appetite counteract the passions of the concupiscible appetite: since the concupiscence, on being aroused, diminishes anger; and anger being roused, diminishes concupiscence in many cases.
Unde etiam passiones irascibilis repugnare videntur passionibus concupiscibilis, nam concupiscentia accensa minuit iram, et ira accensa minuit concupiscentiam, ut in pluribus.
This is clear also from the fact that the irascible is, as it were, the champion and defender of the concupiscible when it rises up against what hinders the acquisition of the suitable things which the concupiscible desires, or against what inflicts harm, from which the concupiscible flies.
Patet etiam ex hoc, quod irascibilis est quasi propugnatrix et defensatrix concupiscibilis, dum insurgit contra ea quae impediunt convenientia, quae concupiscibilis appetit, et ingerunt nociva, quae concupiscibilis refugit.
And for this reason all the passions of the irascible appetite rise from the passions of the concupiscible appetite and terminate in them; for instance, anger rises from sadness, and having wrought vengeance, terminates in joy. For this reason also the quarrels of animals are about things concupiscible--namely, food and sex, as the Philosopher says [De Animal. Histor. viii.].
Et propter hoc, omnes passiones irascibilis incipiunt a passionibus concupiscibilis, et in eas terminantur; sicut ira nascitur ex illata tristitia, et vindictam inferens, in laetitiam terminatur. Propter hoc etiam pugnae animalium sunt de concupiscibilibus, scilicet de cibis et venereis, ut dicitur in VIII de animalibus.