The large pink and white flowers pictured here are Oenothera speciosa, also known as Pink Ladies. Some folks call them showy primroses or prairie primroses. Whatever common name you choose, these members of the Evening Primrose family (Onagraceae) are beautiful with their pink and white petals and yellow near the center of the flower.
Each flower has 4 broad petals and they are fragile and easily damaged. Within this species, petal color can range from rosy pink to nearly all white in color. Their alternately arranged leaves are 2 to 3 inches long and have coarsely toothed margins. Also, you will sometimes see that the leaves can be deeply lobed making them appear pinnately compound. This kind of leaf shape is called pinnatifid.
Primroses of all kinds have very distinctive long anthers on their stamens. The tops of their Pistils form a cross. These characters along with the 4 petaled flowers help make these prolific plants easy to identify.
In both images, you can also see a single bloom of Pyrrhopappus pauciflorus, the Small-flower Desert Chicory. Some folks call this member of the Daisy family (Asteraceae) the Texas Dandelion. The diameter of the flower pictured is between 1.5 and 2 inches which is much larger than your regular dandelion. Additionally, this species gets taller than regular dandelions. Unlike other Asteraceae, Texas Dandelions lack a button or disk flowers in the center of their blooms; instead, they only make the ray flowers, the ones with petals. As a result, Small-flower Desert Chicory look like larger versions of the familiar dandelion.