Internal gland organ with distinct tissues with different endocrine and exocrine functions. Its rudiment has three parts, one dorsal and two ventral primordia. The ventral can be first detected at NF stage 37/38. The dorsal is clearly segregated from the duodenal wall by NF stage 39. At NF stage 40 the right and left primordia have fused just above the gastro-duodenal vein. At NF stage 42 blood vessels penetrate into the crevices between the pancreatic acini making them more conspicuous.