For the vinaigrette: Place the raspberries, olive oil, lemon juice, and honey in a blender. Blend until smooth. Season with salt and pepper, to taste.
In a large salad bowl, mix together the lettuce, arugula, and pumpkin seeds. Just before serving, add the vinaigrette and toss until all the ingredients are coated.
Cook's Note: To toast the pumpkin seeds, arrange in a single layer on a baking sheet. Bake in a preheated 350 degrees F oven until lightly golden, 6 to 8 minutes. Cool completely before using.