pets and plants
The short answer to your question depends upon what you mean when you ask about the common names of the plants. According to the ASPCA, ivy and caladiums are toxic to dogs but Christmas cactus is not.
The long answer is:
Ivy's common names: English, Branching, Glacier, Needlepoint, Sweetheart, and California
Scientific Name: Hedera helix
Toxic Principles: Triterpenoid saponins (hederagenin)
Clinical Signs: Vomiting, abdominal pain, hypersalivation, diarrhea. Foliage is more toxic than berries.
Toxicity: Toxic to dogs, cats, and horses
Caladium's common names: Malanga, Elephant's Ears, Stoplight, Seagull, Mother-in-Law Plant, Pink Cloud, Texas Wonder, Angel-Wings, Exposition, Candidum, Fancy-leaved Caladium
Scientific Name: Caladium hortulanum
Clinical Signs: Oral irritation; intense burning and irritation of month, tongue, and lips; excessive drooling; vomiting; difficulty swallowing.
Toxicity: Toxic to dogs and cats
Christmas Cactus's common names: Easter Cactus
Scientific Name: Schlumbergera bridgesii
Toxicity: non-toxic to dogs and cats.
However, keep in mind that like people, animals may have allergies unique to them and may in fact exhibit some symptoms of irritation even when a particular plant is not categorized as toxic to their species. Therefore, the safest option is to limit their ability to ingest anything not meant for their consumption.