--- a
+++ b/singlecellmultiomics/modularDemultiplexer/demultiplexModules/CELSeq1.py
@@ -0,0 +1,24 @@
+from singlecellmultiomics.modularDemultiplexer.baseDemultiplexMethods import UmiBarcodeDemuxMethod
+
+
+# Cell seq 1 with 6bp UMI
+class CELSeq1_c8_u4(UmiBarcodeDemuxMethod):
+    def __init__(self, barcodeFileParser, **kwargs):
+        self.barcodeFileAlias = 'celseq1'
+        UmiBarcodeDemuxMethod.__init__(
+            self,
+            umiRead=0,
+            umiStart=8,
+            umiLength=4,
+            barcodeRead=0,
+            barcodeStart=0,
+            barcodeLength=8,
+            random_primer_read=1,
+            random_primer_length=6,
+            barcodeFileAlias=self.barcodeFileAlias,
+            barcodeFileParser=barcodeFileParser,
+            **kwargs)
+        self.shortName = 'CS1C8U4'
+        self.longName = 'CELSeq 1, CB: 8bp, UMI: 4bp'
+        self.autoDetectable = True
+        self.description = 'R1 starts with a 8bp cell barcode followed by a 4bp UMI. R2 ends with a 6bp random primer'