Make a comparison between cancer and arachnids.

Crustaceans:
1. Body size from fractions of mm to 3 m
2.Departments of the body – cephalothorax, abdomen
3.Number of antennae – two pairs
4.Number of mouth limbs – three pairs
5.Mouth apparatus – gnawing
6 respiratory organs – gills
7 excretory system – a pair of green glands

Arachnids:
1. Body size from 0.2 mm to 20 cm
2.Departments of the body – cephalothorax, abdomen
3.Number of antennae – absent
4.Number of mouth limbs – two pairs
5.Mouth apparatus – sucking
6 respiratory organs – pulmonary sacs and trachea
7.Excretory system – Malpighian vessels